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AC Condenser Guide: Costs For Replacing In a Home Air Conditioner

Your air conditioning system has three major components. The first two, the evaporator and compressor, work to get the cool air into your home. The third, the condenser, is considered to be the central portion of the entire system. Without the condenser, your house wouldn’t heat or cool at all.

How much does a condenser cost to replace? How can you tell if it is going bad? This article will answer those questions as well as identifying the parts, system expectations, and if a replacement should be a DIY or professional project.

How the Condensing Unit Works

The condensing unit is generally outside unless you have an enclosed unit. With most residential and commercial applications, though, a split AC will have the evaporator unit inside and the condenser unit outside.

The refrigerant is brought into the condenser through the low-pressure line as a hot liquid. It travels through the coils where the air is passed over to begin cooling it down. The coolant then passes through the coils and to the compressor, which is found inside the condenser unit, below the fan.

The compressor turns the low-pressure liquid into a high-pressure vapor and passes it through the rest of the condenser coils to finish the cooling process. From there, it is sent off to the evaporator unit, and the cycle repeats.

Types of AC Condenser Units

There are three types of condenser units available, water-cooled, air-cooled, and evaporative. Let’s take a look at the three to find the best option for your home.

Water-Cooled

Water-cooled condensers use tubing to pass water through the system. The water removes the heat from the refrigerant and passes it to the ambient air outside. There are three types of tubing, known as shell and tube, shell and coil, and dual-tubed.

Each similarly manages the process, warm water goes out, and cool water returns. The cool water absorbs the heat from the refrigerant during a heat-exchange inside the condenser. The water-cooled condensers are the most efficient, although they also cost the most to install.

Air-Cooled

Air-cooled condensers are primarily used in residential and small commercial areas. If you have a split AC, you most likely have an air-cooled condenser. The main difference here is that air is drawn in from the ambient space around the condenser over the coils. The hot refrigerant inside is cooled down, and the heated air is pushed out (generally through the top).

Air-cooled units are considerably cheaper to install but come at the cost of a higher monthly energy bill. They are not as efficient at cooling as a water-cooled unit, so they have to run longer to produce the same amount of cooling inside the home.

Evaporative

For what it matters, an evaporative condenser is a hybrid of a water and air-cooled unit. They are cheaper to install than water units, more efficient than air units, and last longer than both other types combined.

However, because they are such a large capacity condenser, you will only ever really find them in industrial and large commercial usage. While they can work with any AC system, placing these types of units in a residential setting isn’t feasible.

AC diagram outside unit

Replaceable Parts of AC Condensers

Condensers are made up of several different parts, each with a specific job to do. Let’s take a look at these parts and find out what they do.

Condenser Coils

Condenser coils are responsible for taking the heat out of the compressed refrigerant vapor. As the vapor travels through the coils, the air blowing over them causes a heat transfer that rapidly cools the refrigerant, resulting in the vapor turning into a liquid.

Condensate Pump

As the heat exchange takes place, condensation will form and be pulled to the bottom of the system. A condensate pump is triggered when the water level gets too high and pumps the water out. An impeller on the bottom of the pump removes the water and flushes it from the system.

Condenser Fan Motor

The fan motor is mounted to the top lid of the condenser unit and turns on whenever the system has power. The motor is responsible for spinning the fan blades, which work to remove the hot air from inside the condenser. They pull colder air in from the sides of the unit to cool the refrigerant running through the coils.

Condensate Drain Line

The condensate drain line is simply what it sounds like. As the condensation is pumped out from the condensation pump, it travels through the condensate drain line to exit the system.

Condenser Pad

The condenser pad is a concrete or composite square that acts as the base for the condenser. It works to give the condenser a solid, flat surface to mount to as well as lifting the unit off the ground to keep it from collecting debris from the yard.

Condenser Relay Switch/ Run Start Capacitor

A relay switch is more often referred to as a contactor. It is responsible for providing the current for switching the high voltage components on and off. The contactor is connected to the run capacitor, which gives it the jolt needed to engage the electromagnetic switches.

Without a run capacitor, the system wouldn’t get enough voltage to kick on, the compressor wouldn’t operate, and the blower and condenser fans wouldn’t spin. Without a contactor or condenser relay switch, the system wouldn’t stay running.

Common AC Condenser Problems

The condenser is generally a well-running piece of the HVAC system. However, because of the high voltage required to run it, the moving parts and heat exchange, things will go wrong. Let’s look at the more common failure points of the AC condenser.

Dirty Components

When dirt and debris enter the system or its components, it has to work harder to produce the same cold air you are used to. You should inspect your condenser regularly and keep the coils, fan, and air louvers clean and clear of dirt, debris, or build up.

Leaks

If the unit is leaking, you will need to replace the part that is leaking. The two primary leaking spots are refrigerant escaping from the fill valves and from a bad compressor. If you notice the level of your refrigerant is dropping, check the valve cores. They can be replaced with a valve core tool designed for air conditioners.

If the compressor is rusted or has otherwise gone bad, it can leak from the bottom or the copper tube connections. The tubing can be brazed to patch a small hole, but a large hole or bad compressor will need to be replaced entirely.

Blockages

If debris is allowed to enter the system, it can block off the coils. This is a sign of a faulty line dryer filter. You may also notice the coils aren’t being cooled or that the system never shuts off. This is generally an indication that the air louvers on the outside of the condenser are packed with debris, leaves or yard waste.

You can have your system flushed and a new filter dryer put in place to unclog the coils. If the flush doesn’t work, you will need to replace them. For blocked louvers, a garden hose will keep them clean.

Damaged Coil

Just like an internal blockage from debris, the coils can be pressed inward on themselves. Touching the coils can cause this, as well as flying debris during a storm. If the coils are damaged, it is generally best to have the system inspected before jumping to a coil replacement.

Bad Run Capacitor

The run capacitor is usually the first part to fail. You will notice a bad capacitor because it will be swollen. Capacitors also have a tale-tell color ring. If you look at the top of the capacitor and see a yellow circle that looks like a tiny coffee mug stain, this usually indicates the fluid inside is leaking. A swollen or leaking capacitor needs to be replaced immediately.

Bad Condenser Relay Switch

Second, to the capacitor, the relay switch also burns out over time. You will notice a faint burns metal odor coming from your condenser. When you open the access panel, you will see the copper coils on the electromagnet of the contactor have been burned. When this happens, it is time to replace the relay switch.

Faulty Control Board

Some newer model air conditioners use a computer control board to send the voltage and control the operation of the unit. With the exception of the capacitor, everything is done through the solid-state control board. Control boards can burn out or have issues, as well. Usually, when this happens, you will get an error code on the AC display.

Your first option should always be to call the company or retailer where you purchased your unit to make sure the error codes point to the control board and that your unit is not in warranty. If it is not in warranty, you can replace your control board as a DIY project.

Burned-Out Motor

Motors will wear out eventually, and this can cause more significant problems if left untreated. Your first stop should always be the contactor and capacitor as they provide the power to the condenser fan. If these are in working order, then the fan motor is generally to blame.

When purchasing a new fan motor, you will need to ensure you get the same voltage, rotation direction, and input capacity of your existing motor. All of the required information can be found on the paper label glued to the motor itself.

Symptoms of a Failing AC Condenser

Because there are many different parts of the condenser unit, it is hard to tell if the condenser has failed. It could be another portion of the condensing and compression stage of the cooling process. Here are the notable symptoms of a failing AC condenser.

Significantly Reduced Cooling

When you set the temperature on your thermostat, you expect your house to get to that temperature in a reasonable amount of time. If the cooling takes a lot longer to reach temperature, it could be the condenser’s fault.

Usually, when the air isn’t cold enough, the first thing you want to check is the common failure points. The air filter and thermostat are the most likely culprits. However, if these check out, it is time to inspect your condenser unit. Most often, the problem is debris build up in the air louvers. A good rinse with a hose will clear the issue.

If the problem persists, you will need to hire a professional to run flush tests and inspect the coils with testing equipment.

Noticeable Leaks

If you notice a lot of water around your condenser unit, it isn’t leaking. Refrigerant is the only thing running through the system, and it won’t puddle. The exception is if you have a water-cooled unit, and the leaking water is generally too hot to pool. Instead, it will burn off and evaporate.

The vapor will whistle as is escapes and will empty into the atmosphere. If you suspect your condenser is leaking, you should look for the vapor clouds and listen for the whistle when the AC is on.

If you see a puddle, this is generally the result of melting ice. Ice will build-up on the copper lines and can even encase the compressor. This is a sure sign of a leak in refrigerant and a loss of pressure. In this instance, you will need to refill your refrigerant level and locate the leak. A blown fill valve core is the most likely place to look.

Defective AC Condenser Fan Motor

Another sign of a bad condenser is when the motor for the condenser fan doesn’t operate as expected. The Fan motor can seize, run intermittently, or run continuously. If the motor doesn’t run at all, it will cause your condenser and compressor to overheat.

Any other unexpected fan motor operation is a sign of a lousy contactor or capacitor. An inspection of these two items, or replacement, is recommended.

Factors to Consider When to Repair or Replace Condenser Coils

When something goes wrong, you have the option to repair the issue or replace the part. How should you base your decision? Let’s take a look at some examples to find out.

Systems Age

Age plays a key role in the efficiency and cost-effectiveness of your HVAC system. Most residential systems will be reliable for about 20 years. If your condenser is only a few years old, it isn’t economical to replace the entire unit. You can repair a condenser for a lower cost if the part is still in warranty.

However, if your unit is getting up there in age, it may be more beneficial in the long run to replace the entire unit with a new one.

Efficiency Upgrade

Newer systems require less maintenance and are designed to last longer. You may be interested in upgrading your system to integrate with your smart home, for example. Since older systems don’t have the capabilities required for smart home integration, you may decide to purchase an upgraded unit.

Older R22 Systems

R-22 refrigerant is no longer being produced. What is available for purchase will be gone soon. In the meantime, prices for R-22 are skyrocketing. Even though you won’t be able to buy the refrigerant yourself (you must have a certification license), the additional costs will be added to your maintenance bill.

Moving to a newer system that uses an approved refrigerant like R-410a, is not only better for the environment, but will also keep more bills in your wallet in the long run.

AC Condenser Replacement & Repair Costs

How much is it going to cost to repair or replace your AC condenser? This section will cover various parts, brands, and options to give you a better idea of what your costs will be.

Keep in mind that each region, area, and situation will have various nuances that will affect the final cost. Be sure you always get at least three quotes before settling on a final purchase option.

Home AC Condenser Parts Replacement & Repair Costs

The condenser unit is a simple system with a lot of intricate parts. The diagnosis of the component causing the problem is the first hurdle. The most significant causes of condenser unit failure are the coils, fan motor, circuit control board, contactor or capacitor, and blockages or leaks.

When hiring a professional, the costs will increase at last double. Most professional repair companies will charge an hourly labor fee, which can range between $50 and $150 per hour.

Home Advisor breaks down the common failure points based on size (coils and condenser unit ton-capacity). This information is expressed in the chart below.

Size Unit Price Total With Labor
1.5 – 2 Ton $500-$800 $900-$1,500
2.5 Ton $600-$1,000 $1,000-$2,200
3 Ton $700-$1,100 $1,100-$2,300
3.5 Ton $750-$1,200 $1,150-$2,400
4 Ton $800-$1,300 $1,200-$2,500
5 Ton $1,000-$1,600 $1,400-$2,800

Chart information retrieved from Home Advisor

Unless you have a blockage or a leak, repairs can be done by the replacement of worn parts. Instead of replacing the entire condenser unit, you can expect to pay the following costs for the various common failure parts. Note, the chart below does not include labor.

Part Cost
Motor $350-$600
Control Circuit Board $150-$400
Contactor or Capacitor $150-$300

For a blockage or a leak, it is highly recommended that you replace the entire condenser unit. Costs for those based on brand, size, and application are below.

Residential HVAC Condenser Unit Replacement Price by Brand

If you are going to replace the entire condenser unit, there are a few factors you must decide on before making your purchase. First and foremost is the type of refrigerant being used by the system. If you currently use R-22 and want to go with a system that uses R-410a, you will need to also replace the high-pressure line and flush the entire system before installation.

The size of the condenser unit is also required. If you put a condensers that is too big for your system you won’t run efficiently and the costs on your energy bill will increase. Likewise, if you opt for a condenser that is too small, the system will have to work overtime to cool your home, resulting in a shortened life span and a higher monthly energy bill.

Most residential homes average a 1.5 – 2-ton unit. The ton measurement comes from how much heat it takes to melt one ton of ice. This was adapted into the BTU measurement we use today, but condensers are still rated by tons. Below are costs for condenser units, by brand, for an average residential installation.

Condenser Brand 1.5 ton/ R-401a Cost
Goodman 1.5 ton/ R-401a $$
Trane 3 ton/R-410a $$$
Carrier 1.5 ton/R-410a $
Lennox 2 ton/R-410a $$
Rheem 2 ton/R-410a $$

DIY Vs Professional HVAC Technician

Before you jump in and start fixing things yourself, you need to understand the dangers involved. First, you are dealing with an energized electrical component that deals with temperature extremes.

3rd-degree burns, as well as frostbite, are all possible with improper handling. You are also going to be messing with parts that generally have over 200 volts of electricity running through them. Always double-check power supplies are shut off, safety gear is worn, and that you know exactly what you are doing.

While the dangers are serious, most repairs and replacements aren’t that complicated. You will have to handle refrigerant, though, which does require a license. If you do not have a license, you can attend a class to get certified. Check the EPA guidelines for details.

Hiring a professional will save you a lot of time and headaches. However, labor costs can get high. For routine maintenance, you should do it yourself (see further below). Replacing the relay switches, capacitors, and even the blower motors can be done as a DIY project. Beyond that, though, it is beneficial to hire a professional.

You can check Angie’s List for reputable professionals in your area.

How to Replace AC Condenser Units

Before you set out to replace your condenser unit, you will need to have an understanding of the HVAC system, how it operates, and the refrigerant it uses. You will also be required by law to have a license to handle the refrigerant.

  • Before you remove the power to the condenser, you will need to recover the refrigerant that is in the system. This will require a recovery machine, refrigerant gauges and manifold set, recovery tank, and protective equipment.
  • Remove the disconnect block form the outside power breaker and short the capacitor to drain any residual charge.
  • Close the refrigerant valves to prevent any leaking from leftover vapor in the compressor.
  • Cut the copper refrigerant lines at the condenser, leaving enough behind to braze the new condenser unit into.
  • Disconnect the thermostat wires, power wires, and junction box wires from the condenser.
  • Remove the top shell and pull out the fan and fan motor.
  • Assuming your new condenser unit comes with a compressor, you won’t need to remove the old one. If you are using the old compressor, you will need to remove it as well.
  • Unbolt the condenser unit from the pad by removing the bolts from inside the unit.
  • Carefully remove the condenser unit from the pad and recycle where applicable.
  • Installation of the new condenser unit is the reverse of removal.

How To Clean Condenser Units

Cleaning your AC condenser unit should be an annual routine. You can also maintain the unit seasonally to help the overall upkeep. Maintenance should take you about an hour, though you will get faster with knowledge and practice.

The idea behind the maintenance is to keep the unit working efficiently. You will be checking for damage, removing debris and clearing the area of possible airflow blockades. You will need a screwdriver with a Phillips, flat, and ¼ drive ends. Most 4-in-1 screwdrivers will fit all of the screws on your condenser.

You will also need a garden hose with a nozzle attachment, eye protection, gloves, and either a shop vacuum or air compressor.

Important Note: Any time you are working in, on, or around the condenser unit, you must shut off the power. You can pull the power disconnect block (or toggle the on/off switch to off). However, you should be cautious as many components inside retain the electricity they store. Even with the power off, sudden jolts of component movement are still possible.

  • The first thing you need to do is clear the area around the condenser and pad. Use yard tools to cut down grass, weeds, and any other lawn debris that can grow up, in or over the condenser.
  • Blow or vacuum the fins and air louvers on the outside of the unit. Pay special attention to the corners and bottom of the condenser shell.
  • Inspect the fins and ensure they are straight and parallel. You can use a small knife to straighten the fins if needed.
  • Remove the top of the condenser shell with the fan and fan motor attached. Go slow, as there won’t be a lot of room because of the electrical wires. Place the top securely out of your way to give you access to the inside.
  • Spray the inside of the unit with the garden hose and nozzle. Moderate pressure should be used. From inside, direct your spray to the outside of the machine, cleaning out the coils and fins from top to bottom.
  • Vacuum out the inside bottom area around the compressor and the pad underneath.
  • Reinstall the fan and shell top using all of the mounting screws you removed and ensuring the electrical wires do not become pinched, cut, or dislodged.
  • Go around the unit again, clearing off the debris expelled from spraying in the previous steps. Do not spray back into the machine. If stubborn debris is present, use the vacuum to remove.
  • Replace the air filter inside your home and set the thermostat for the AC to come on.
  • Restore power to the condenser and ensure everything is in working order.

Frequently Asked Questions

Let’s go over a few of the more common questions about the AC condenser and its various pieces.

How long do AC coils last?

With proper maintenance and care, the coils in an AC condenser should last several decades. Because the coils are a closed system, unless there is physical damage from an outside source, the coils should last at least as long as the rest of your HVAC system.

How long should I expect my AC condenser to last?

The average life expectancy for a home AC condenser is about 20 years. This can be extended with proper and routine maintenance. For automotive compressors, life expectancy is about five years, depending on usage.

Do home warranties cover AC coil replacement and repairs?

Most home warranty companies will cover the HVAC system, which will include the AC coils. However, we can’t know every home warranty option available as well as each company’s practices. You should double-check with your home warranty company as to what is covered and to what degree before any work is done.

Is it more economical to buy a whole new system vs. repairing and replacing my AC condenser unit?

This will depend mostly on the age of your AC system as well as which parts are being replaced. It is also a consideration if you are doing the repairs or replacement yourself, or hiring a professional. Unless you are EPA certified, a professional will be required for legal reasons in most cases.

How much does an AC condenser unit typically cost?

The cost will vary significantly from brand to brand. You will need to factor in the size and capacity of the condenser unit, brand, refrigerant type, installation location, etc. For just the parts, though, most residential AC compressors will range between $500 and $2,000.

Conclusion

While budget is a major factor when deciding to repair or replace your condenser unit, it is also a factor in whether the job will be done as a DIY project or by a professional. It is always advised to hire out the work when dealing with major AC components such as the condenser.

Because of the dangers involved and the EPA license requirements, most homeowners aren’t legally allowed to work on their own systems. This doesn’t mean you can’t maintain the system and replace smaller parts that go bad yourself, but it should be considered.

The overall costs of hiring a professional versus doing the job yourself are mostly minimal. When you factor in your time and the warranties, the labor costs can be considered a wash.

by Joshm Joshm No Comments

AC Capacitor Cost: Price Guide For Replacing In a Home Air Conditioner

Your AC capacitor is a small but essential part. Several other AC components require the kick start a capacitor offers, such as the compressor, the fan motor, and the blower. If your capacitor goes bad or begins to wear out, your air conditioner won’t function properly or will cycle on and off many times in a continuous manner.

This article will look at the various types of AC capacitors and help you diagnose the problem, show you the different capacitor types, and help you replace your capacitor, including the cost to do so.

AC repairman

How AC Capacitors Work

A capacitor is a piece of electrical equipment that stores energy. It is connected to the condensing unit power supply (220V) and collects energy until it is needed. When the air conditioner needs to come on, the capacitor sends a high-voltage jolt (upwards of 400 to 600 volts) to the compressor, fan motor, and blower motor. They operate in a similar way to a car’s alternator.

Once the capacitor has started the components, your AC will come alive and begin blowing cold air. During the run cycle, the capacitor stores a new supply of energy while maintaining a constant flow to keep the other parts moving.

Most AC systems will have two capacitors. The primary capacitor in the condensing unit will power the compressor and the condenser fan motor. The secondary capacitor is generally smaller and will operate the blower motor in the evaporator unit.

Smaller AC units can run on a single capacitor while newer, larger systems will require three. Your system’s manual will tell you how many and which type of capacitors it requires.

Types of AC Capacitors

Generally speaking, there are two types of capacitors, start and run. Both types also have sub-types. Let’s take a look at the various types of AC capacitors.

Start Capacitor

A start capacitor produces the electricity needed to start an electromagnetic motor. A blower motor, for example, will require the jolt from a start capacitor to produce enough energy to begin rotation.

Start capacitors only engage long enough to get the motor running and then disengage; waiting until the next time they are needed. Each start capacitor has a capacitance measured in microfarads (µF), which we will cover further below. Microfarads are also labeled as MFD. This is important to note when looking for a new capacitor. MFD and µF are the same in this situation.

A Super Boost Capacitor/Turbo Capacitor isn’t technically a capacitor. They are also known as a hard start capacitor. The kit is designed to offer an even larger boost to get a motor running and will connect directly to the ports on the start capacitor. These are usually needed in rare situations when the compressor won’t start, or there is an electrical problem.

They are not designed to be installed and forgotten. Instead, they are made to help the AC system work to diagnose other problems or to get a new install up and going.

Run Capacitor

wiring diagram AC capacitorIn your home AC, you will find a run capacitor is used more than a start capacitor.

A run capacitor operates whenever the system is on to help create the magnetic field that keeps coil motors moving.

There are two main sub-types of run capacitors.

A single-stage run capacitor will start and power a single motor or device. In our situation, this will be used to run the blower motor or the fan motor.

However, it is more likely that your condensing unit uses a dual-stage run capacitor.

You can tell because single-stage capacitors have two terminals on the top while a dual-stage capacitor has three.

Signs of a Bad AC Capacitor

The downside to an AC that isn’t functioning correctly is that several parts could be the underlying problem. For example, an AC not blowing cold air but otherwise operating fine could be the result of a bad compressor, a bad capacitor, or even a dirty air filter. Therefore the diagnosis is needed to determine the root cause of the issue. Here are some signs your capacitor is going bad or has failed.

AC Not Blowing Cold Air

As we mentioned above, this could be caused by another part of the system. An air conditioner not blowing cold air will only increase your energy bill. The run capacitor could be the culprit here, and if the air from your AC vents isn’t cold, check to see if the compressor is running.

If the compressor or the fan in the condensing unit is not running, they could be the problem. However, if both are not operating, it is most likely the run capacitor that is faulty.

High and Rising Energy Bills

When the HVAC system seems to be running fine, but you have noticed your energy bill increasing each month, your capacitor could be at fault. A capacitor doesn’t work one cycle and then fail the next. Instead, they get worse and worse as time goes on until they can no longer store enough power to start the system.

While they are still functional but going bad, the AC will run for shorter periods, causing it to cycle on more often. This increase in running times will cause your energy bill to spike.

Humming Noise

A common sign of imminent failure is a light humming noise coming from your condensing unit, even when it isn’t running. You can remove the access panel to the compartment that houses the capacitor. If the humming gets louder, it is most likely the capacitor beginning to short out.

Old HVAC System

Age is another concern. A run capacitor has a life expectancy of about 15 to 20 years. However, areas that are warmer longer, like the southwest, will have a shorter life span for their capacitors because they are used and cycled more frequently. If your HVAC system has at least ten years of operation, the capacitor could be starting to fail.

AC Turns Off or On Its Own

We set our thermostats to a desired temperature for our comfort. The expectation is that when the temperature rises above this point, the air conditioner will come on. Once the set temperature is reached, the AC will shut off.

If your capacitor is bad or faulty, it can leak the stored electrons into the motors and cause them to turn on, even if the thermostat hasn’t opened the circuit yet. They can also cause the motors to shut off before the desired temperature is met.

AC Doesn’t Turn On Immediately

We also expect our systems to work. When the thermostat opens the circuit, the compressor and condenser fan should start up immediately. The blower motor in the evaporator unit may take some time to come on, though, so be aware.

Most blower motors are connected to a time delay switch that won’t allow the power to the motor for up to five minutes. However, if the AC is turned on, and the compressor takes more than 30 seconds to start, your capacitor could be to blame.

AC Won’t Turn On

If the above situation isn’t remedied, eventually, the capacitor will get to the point where it can’t power the system at all. When this happens, the AC won’t turn on at all. While this could be due to other factors, such as a worn-out compressor or a faulty thermostat, the most likely candidate is the capacitor.

Common Causes of AC Capacitor Failure

Just as there are many different signs that your capacitor is bad, there are also many different causes. The most common cause is age. As I mentioned earlier, the life expectancy of a run capacitor is about 20 years. The more an AC is used, the lower the age range becomes. However, if your capacitor is over ten years old and the system starts to act funny, the capacitor is the most common culprit.

Another cause of failure is heat. While it may sound counter-intuitive, a hot summer day can cause your capacitor to overheat. It is advised to keep your condensing unit in the shade during the hottest parts of the day.

As long as there is room around the unit for proper airflow, shade trees and shrubs can go a long way to prolonging the life of the electrical components inside the condenser, including the capacitor.

Finally, the voltage going to and from the capacitor must be within range. Each capacitor has a voltage rating, and if this is exceeded (or to some extent undervalued by a great deal), the capacitor can fail.

AC Capacitor Replacement & Repair Costs

Replacing your AC capacitor doesn’t have to cost an arm and a leg. As a DIY project (details further below), you will only pay for the capacitor itself. The price range will vary depending on a few factors, such as the brand, capacitance, and size of the capacitor you need. However, you should expect to pay between $5 and $30 for the part.

If you don’t want to take on the job yourself, you can hire a professional. According to Home Advisor, the average cost for a home visit, inspection of the system, and replacement of the capacitor will range from $90 to $400. This will include labor and parts. The entire job should take less than 30 minutes.

If you do hire out a professional, be sure to get a minimum of three quotes before you hire someone to do the job. You can check Angie’s List for recommendations of reliable professionals if you don’t have an electrician or HVAC repair specialist you know and trust.

Choosing Replacement Capacitors

When you have diagnosed the system and found the capacitor to blame, it is time to replace it. There are not parts of a capacitor that can be repaired, so once it fails or begins to fail, the only option is a replacement. Here are things to look for in a replacement capacitor.

Original Capacitor Voltage

Voltage is critical to the capacitor and the system. You must find one that has a voltage range capacity that matches your system. Each capacitor will have the voltage ratings printed on the side of the canister, as well as the packaging. If your capacitor is too old and the writing has worn off, your HVAC owner’s manual will tell you the proper voltage for your capacitors.

Original Capacitance Value

The capacitance value is measured in microfarads (µF). Run capacitors can range from 1.5 to 100 µF. A start capacitor will range from 70 up to 200 µF, and even higher for some commercial situations.

You must ensure that the microfarad rating is a match for your system. If it is not, the system may start by the motors will not have the proper magnetic shielding and will burn out or not run fast enough.

Frequency of Operation

Knowing how often you run your HVAC system on average will also help you determine which capacitor to purchase.

Overall Shape & Size of Capacitor

There are several sizes and shapes of capacitors, and getting the right one for your system is crucial. Primarily, a home AC will use a round or oval-shaped capacitor. These vary in length, but two to four inches is standard.

Before you purchase a new capacitor, you should look at the current one that is installed. It will be mounted to the inside of the access area of the condensing unit with a metal strap and a screw. There isn’t a lot of wiggle room inside this panel for larger capacitors. You can switch between oval and round, as long as you have the space for it.

You may need to replace the metal mounting strap for a longer piece if you switch to an oval-shaped capacitor, or to tighten the existing strap if going to the smaller cylindrical type.

Terminal Type

Another factor to consider is the terminal type. A majority of homeowners won’t have to worry too much about this, as run capacitors use a male-end plug that slips into a female connector.

Some older models are the opposite, though, with the capacitor having the female leads and the wires using the male terminators. You will have to look at your capacitor to determine which style your unit has.

AC Capacitor Replacement Products

To get you started with your replacement research, I have compiled several brands, sizes, and types of capacitors for you to choose from. Remember that your capacitor must fit your system in size, voltage, and range.

Special note: While some run capacitors are rated and branded for a specific use, you do not have to stick to a particular brand. Just because a capacitor is a direct replacement for a Trane, for example, doesn’t mean it won’t work in a Goodman unit. As long as the voltage and MFD ratings are the same, the capacitor will work just fine.

To read the ratings, there are two numbers to be on the lookout for. All capacitors will have the MFD rating range. This will appear as two numbers split by a forward slash or sometimes a positive and negative symbol. For example, the Carrier capacitor, first on the list below, has an MFD of 45/5. This means it produces 45 µF with a variance of +5.

The second number after the slash is the variable in change. It shows how much discrepancy there is between the lowest and highest output. In this case, the 45 µF can be as low as 40 or as high as 50. If your capacitor rating is between 40 and 50, this capacitor will work for you.

Run Capacitors

1. Carrier 45/5 Dual Run Capacitor – Round

This model is a direct replacement for most Carrier models. Before you purchase, you should double-check the voltage and output ratings of your AC and ensure they match the capacitor.

2. HVACPartsUSA – 80/7.5 Dual Run Capacitor – Oval

The 80/7.5 capacitor sold by HVACPartsUSA is an oval capacitor that will fit most Lennox units. If you want or need an oval capacitor, this one will work in most systems. As always, be sure to double-check the voltage and capacitance ratings prior to purchase.

3. Universal 10/5 Dual Run Capacitor – Round

If you aren’t concerned with a name brand match, this universal capacitor will fit a wide variety of models. The 10/5 MFD will replace most 12 SEER and older models.

4. ClimaTek 45/5 Dual Run Capacitor – Round

The Climatek capacitor is made for Trane parts replacement. However, with a 45/5 MFD and 440volt capacitance, it will also fit most modern AC systems up to 14 SEER.

Start Capacitors

1. Electrolytic Start Capacitor 108/130 Start Capacitor – Round

A lot of start capacitors can be replaced with this 108-130 MFD range round capacitor. Double-check your ratings and ensure you need a capacitor with a voltage output of 125.

2. Trane CPT00091 Start Capacitor – Round

Trane motors need a specific amount of voltage. This 330v capacitor fits the bill for a lot of Trane models. It also has an MFD rating of 135 to 162. A list of compatible Trane units is listed in the description.

DIY vs Professional HVAC Technician

It is never a bad idea to call a professional if you are ever in doubt or uncomfortable working on your own air conditioner. There are a lot of dangers that must be prepared for and expected when dealing with moving electrical parts and high-voltage.

With that being said, you can save yourself hundreds of dollars by replacing the capacitor yourself. You only need a few tools and about 15 minutes of your time to get your AC system back in proper working order.

If you are interested in a DIY project, see below for more details on how to replace a capacitor. For those that cannot be bothered or are too wary of attempting the job, you should look for a professional to get the job done. Angie’s List is a great place to find a licensed professional with a good reputation and acceptable labor charges.

When hiring a professional, make sure you get at least three quotes and know exactly what process they will take when caring for your HVAC system.

How to Replace AC Capacitors

If you have decided to take on the capacitor replacement yourself, there are a few tools you will need:

  • A multi-tipped, electrician’s screwdriver. As long as the grip is rubberized to prevent shocks, you will be fine. It should include a Phillips and flathead. If you do not have a ¼ inch driver bit for the screwdriver, a small socket set will suffice as well.
  • Needle nose pliers, also with rubberized handles.
  • Eye protection. Safety glasses or goggles are a must.

The procedure is a simple one, as well. Remember, though; you are dealing with over 220 volts of electricity. Double-check all breakers and switches are off before opening the access panel.

  • Shut the Ac off at the thermostat, then switch the breaker for the AC. Note: Some breaker boxes have up to four breakers for the AC, often the condensing unit is on its own breaker.
  • Outside, pull the power disconnect block from the breaker panel.
  • Open the access panel. Usually, there are two to four screws that hold the panel in place. Remove the screws and lift up from the bottom then pull out and down to remove.
  • Locate the capacitor. Using a rubber-handle screwdriver short the terminals. Place the tip of the screwdriver on a bare terminal and touch a bare terminal of another post with the shaft of the screwdriver. Repeat for all combinations and terminals.
  • Remove the screw from the metal mounting strip to release the capacitor.
  • Gently pull the capacitor away from the mounting location. Take a photo of the terminals, noting which color wire is connected to the terminal posts. The posts are marked Fan (or just F), Common (or simply C), and Herm (H).
  • Using pliers remove the wire terminals from the capacitor port.
  • Dispose of the old capacitor properly.
  • Push the wire terminals on to the new capacitor ports using the photo from earlier as a guide.

In case you lost the photo or forgot, the general rule is color-coded wires. BE WARNED, not every installation uses the proper color code. This is why it is important to take a photo or draw a diagram before removing the wires. Use the below information only as a guide and not a rule. Every system can be different.

Purple and or red will connect to the common-C post. Bown will link to the fan-F post. Yellow wires will connect to the Herm-H post. Green wires will be a ground wire and not connected to the capacitor. White wires typically don’t appear in AC systems at the condenser; if they do, it is usually a ground wire, especially if a green ground wire is absent. Orange wires will connect to the common-C post.

Also note a start capacitor will be labeled R for Run, S for Start, and C for Common. Red wires will connect to run. Blue wires connect from the contactor to the R or S posts. Brown with white striped wires connect to the Common-C post.

Once the wires are back in place, continue with the installation.

  • Position the capacitor against the mounting area of the access panel.
  • Wrap the metal strap around and secure it to the wall with the mounting screw.
  • Ensure there are no loose wires, or wires laying across contacts or terminals.
  • Restore power to the AC unit and turn on to test.
  • If everything works correctly, attach the access panel cover back in place. For comfort and safety, you should remove the power disconnect block. However, there isn’t a need to also shut off the breakers inside if you are only attaching the panel cover.

If you want to see a video of how easy it can be to replace the capacitor, you can watch this short video:

Frequently Asked Questions

Here I will answer some of the most commonly asked questions about AC capacitors.

Where can I buy replacement AC capacitors?

AC capacitors are found virtually anywhere AC parts are sold. Many local hardware and home improvement stores will have them in stock or available online. Places such as Home Depot, Lowes, and Ace Hardware are ideal resources. You can always find a specific capacitor through Amazon, as well.

Can start capacitors be interchanged with run capacitors?

Technically, you can, as each does, primarily the same job. However, it isn’t advised and can short out your system. A run capacitor is a long term item that runs as long as there is power to the HVAC system. A start capacitor works much like the starter on your car, only engaging when it is needed. Swapping them or using one instead of the other can cause your HVAC system to malfunction or short out, causing further parts to be replaced.

How long do AC capacitors last?

The average expected life span of a capacitor is about 20 years. This will depend on the overall age of the system, ambient temperature, and amount of usage.

How long does it take to discharge an AC capacitor?

If you discharge with an insulated screwdriver, as mentioned in the article, the discharge takes only a second or two. You can also discharge by using a voltmeter, but depending on the size and capacity of the capacitor, this can take some time.

Do home warranties cover AC capacitor replacement and repairs?

This will be up to your specific contract with your home warranty. HVAC systems are tricky when it comes to home warranties, and many cover some parts, but not all. Other companies will cover every bolt and screw in your home. You will need to contact your home warranty company to find out for sure if you are covered when it comes to the AC capacitor or not.

How much does an AC capacitor typically cost?

The actual cost will vary based on brand, size, shape, capacitance, and other factors. You will also receive a mark-up if you hire a professional, and they supply the part. However, in most cases, a dual-run capacitor form your local hardware store should run you between $5 and $30.

Conclusion

A capacitor going bad or burning out can cause your entire HVAC system to be unresponsive. However, a capacitor is an inexpensive part and quickly replaced by most homeowners. Of course, if you don’t want to be bothered with the project or are uncomfortable working around high-voltage, you can always hire an HVAC specialist to replace it for you.

The overall cost is low, and you won’t be without your cold air for very long. A capacitor will range between $5 and $400, which varies for a DIY project and a hired project. The entire process should take less than 30 minutes before cold air is restored.

by jtanner jtanner No Comments

Best Air Conditioner Filters: All Sizes Reviewed & Compared

Best for Central AC

Nordic Pure
Nordic Pure

Most Popular

Filtrete
Filtrete

Made in U.S.A.

FilterBuy
FilterBuy

Air conditioner filters are a crucial part of your HVAC system. Not only will a filter help clean and purify the air moving around your home, but it will also prevent contamination of the HVAC system.

Like almost everything else in life, you have a choice when it comes to the type and brand of your air conditioner filters. This article will examine the various types of filters and their specific abilities to help you decide which air conditioner filter you should purchase.

How Air Filters Work

Nordic Pure how filter worksAir filters have a seemingly simple job; filter the air passing through them. However, the tasks within the job are more involved. First, as the name and job imply, the filter does purify the passing air.

Various types of filters (discussed further below) will take on this job in a myriad of ways. The better the filter, the more particles it will collect.

The main focus though is to keep dirt, dust, and allergens out of the HVAC system. Not only will it help the cooler air being pushed around your home become cleaner, but it will also prevent build-up on the coils and inner workings of the system.

If dirt and dust are allowed to build-up on your evaporator coils or blower fans, air quality will dwindle.

You will also notice that a dirty system will produce foul odors, can clog the drainage pipes resulting in leaks, and can alter the perceived temperature making the system run more than it should.

Types of Air Conditioner Filters

Filters are an ever-evolving material. There are four major types of filters for air conditioners on the market today. Let’s take a look at them now.

Disposable

Disposable filters are among the most common. They are inexpensive, easy to install or remove, and quick to change out. The disposable filters have varying amounts of filter material and can be effective for 30, 60, or 90 days, with some models even lasting up to six months.

Washable/Reusable

Washable filters have stronger filter material and are more expensive than disposable types. However, they will last longer per filter. The main issue found with washable filters is the drying time. Since you should never run your air conditioner without a filter, we recommend buying two. Waiting until your filter is completely dry can cause problems.

Customizable

Unfortunately, not all HVAC systems use the same size filter. Customizable filters fit the bill by allowing you to select the proper size with an adjustable frame. You then cut-to-fit the filter material, replacing as needed.

Deep Pleat

The more filter surface you can have, the longer the filter will last. It will also allow more airflow and clean more particles. Deep pleat filters maximize filter surface area without sacrificing thickness to allow you to double the filter size using the same space.

3 Benefits of HVAC Air Filters

Why should you invest time and effort into selecting the proper air conditioner filter? Here are three reasons to consider.

  1. Purify the air, reducing air born particles and can lower the number of allergens in your home.
  2. Protection for your HVAC system to keep it running properly, longer.
  3. Filters are a reasonable monthly expense that can reduce overall maintenance costs for your entire system.

Air Conditioner Filter Buying Guide

Know exactly what to look for in your next air filter purchase by following the advice in this buying guide.

Filter Size

The size of the filter must be such that it fits snugly in the filter receptacle. Most residential filters will be 1-inch thick but can vary in length and width from eight inches up to 48 inches (or more) and every number in between. There isn’t a one-size-fits-all filter size (exceptions made for customized filter frames), so you will need to measure or refer to your HVAC owner’s manual for the proper size.

Filter Type

Before you make a purchase, you will need to know what type of filter you are going to buy. From the list above, you also have to choose between filter materials. These are things like fiberglass, pleated paper, HEPA, washable electrostatic materials, or even filters containing activated charcoal.

Once you know the type, your air conditioner requires you can narrow down your choices. From there, you will want to look at the filter rating and filtration properties (see below).

Filter Rating

The filter rating is a system that tries to show you a numerical (or colored) value based on how long the filter will last and how many particles it will capture. There are three filter rating systems available: MERV, MPR, and FPR.

The FPR system was developed by Home Depot and is only available on filters they sell in-store. The Micro-Particle Performance Rating (MPR) was developed by 3M to enhance the MERV scale and rates HEPA quality filters (Filtrete and 3M Brands only) that claim to capture in-home allergens down to 1 micron in size.

The Minimum Efficiency Rating Value (MERV) is the original rating system and rates a filter’s ability to capture particles and hold on to them. In all three rating systems, the higher the number, the better the filter material.

Filtration Properties

When you look at the filter’s abilities, the filtration properties are the things you want or need the filter to collect. This can be things like mold and mildew spores, or pet dander, smoke or even odors.

Once you know what particles the filter should prioritize, you can adjust your purchase options. For instance, if no one in the house smokes, there is no need to pay for a filter that will filter out cigarette smoke.

Price

Where budget is a concern, filtration of your air conditioner shouldn’t matter a whole lot. When you spend more, you get more. In most cases, the higher-rated, “better” filters will cost you significantly more than a thin, paper filter designed to fill a hole. However, the price will last you at least 90 days, spreading the cost out over three months instead of every four weeks.

8 of the Best AC Filters Reviewed

Here is our list of the 8 best AC filters reviewed so you can make a more informed purchasing decision.

1. Filtrete

Filtrete is a 3M brand that is known all over the country for their dependable filters and high-quality materials. As an inexpensive disposable filter, Filtrete is one of the best. With an MPR (Filtrete/3M only) rating of 1100, the allergen-reducing filter will help purify your air.

The filter material is not washable and will last up to 90 days. For those in climates or regions with more smoke or smog in the air, you may want to replace the filters every 60 days instead.

2. Nordic Pure

Best Central Air Conditioner Filter

The pleated filters from Nordic Pure are the best option for disposable filters on the market. The MERV score of 12 means that the allergens in your home’s air will be captured, including pet dander, mold, mildew spores, and even pollen.

The cost-effective packs will allow you to have a year’s worth of filtration for the cost of 180 days worth from other brands. If you are looking for the best on a budget, Nordic Pure has you covered.

3. FilterBuy

AC filter made in the usaFor homes that don’t have to worry too much about pollutants such as smoke or smog, the MERV 8 disposable filters from FilterBuy are an exceptional deal. The air will be filtered to keep the return clean as well as prevent dust build-up in the evaporator unit.

These filters are designed to be used with central and split AC systems as well as furnaces. Homes in regions with high pollen counts, or require filtration of cigarette smoke will need a higher quality filter.

4. AIRx Allergy

Best Air Conditioner Filter for Allergen Reduction

If you or anyone in your home suffers allergies, has asthma, or other breathing conditions, your home HVAC filter should be a top priority. Currently, there is none better than the AIRx ALLERGY filter. The AIRx filters are pleated with more surface area than most other pleated brands.

They also have an MPR rating equivalent to Filtrete’s 1200. This will capture smoke, smog, pollen, pet dander and a host of other allergy-inducing pollutants.

5. Honeywell (FC100A1029)

Best Pleated Replacement Filter

For those that have a customized filter or are looking for replacement material for an existing filter, Honeywell is the go-to brand. Not only will the material filter the air for your home and HVAC system, but it is also designed to be replaced in minutes so you can get back to having the air running.

The material is also pleated for a high surface area coverage in a smaller space. When purchasing, ensure your filter area can be covered with the correct amount of material.

6. Trophy Air Electrostatic

If you are looking for a more permanent filter, Trophy Air is the way to go. The electrostatic filter is 100% washable and will dry quickly. You also don’t have to worry about airflow direction as this filter is bi-directional. Once you wash it and let it dry, you can put it back in place in any direction. The electrostatic filtration is completely porous so you won’t block airflow with a reverse installation.

Maintenance is simple, and Trophy Air has updated their sizing availability to ensure you get the perfect fit every time.

7. RV Air (AC 101G)

RV vs other filtersWhen you are on the go in your RV, you don’t need to worry about air quality. The best RV air filter is the RV Air replacement material. It literally takes seconds to replace and will fit most RV air intakes. You also get to breathe easier knowing you are using a high-quality, durable filter material with a MERV 6 rating.

This filter material is ideal for a small space, even if you bring your pets with you. Pollen, pet dander and other larger particles are no match for the RV Air filter material and will not clog your airflow ducting.

8. EPAuto (CP285)

Best Automotive Cabin Air Filter

Most people are unaware that there is a small filter responsible for the air conditioning in their car. Aside from the air and oil filters in your engine compartment, you should also replace your cabin air filter.

The EPAuto filter is ideal for most applications and will provide clog-free airflow while capturing pollutants both internal and external to the car cabin.

Filter Ratings Explained in Detail

The filter ratings will depend on the type and style of filter you purchase. All filters are required to use the MERV rating. However, 3M and Filtrete filters will also have the MPR rating, and Home Depot filters will be labeled with the FPR system.

As we mentioned, all systems use a numbering categorization where higher is better. The MERV system rates filters on a scale of 1 to 16. The higher the number, the more particles (and smaller the particle) the filter collects. Keep in mind that higher MERV numbers mean a denser filter material, which will become clogged with debris a lot faster. You will need to change out higher MERV rated filters more often than lower ones.

The scale doesn’t report on how well a filter performs but instead is the lowest number the filter receives in the worst-case scenario. What that means in laymen’s terms is that the number you see is the worst score possible for that filter, although in practice it will most likely perform better.

Furnace Filter vs. AC Filters: Are They the Same?

The short answer is yes, the furnace and air conditioner will use the same filter. They will at least use the same type of filter. In most cases, a residential system is set up as a central heating and air (HVAC) system.

In these cases, the air return duct is shared by a single unit, and there will be an individual filter. In split systems where the heating furnace is separated from the air conditioner, they will still use the same air inlet ducting, and thus the same filter.

The difference comes in when the systems are stand-alone. In this case, the furnace will use a different filter (two filters total) instead of a shared filter with the AC. However, the filters you purchase for the two units can be the same style and type, although they may not be the same size.

Washable vs. Disposable Filters

Should you go with a disposable, one-time-use filter or a washable one? This really is a personal preference, though your budget may have a say. Washable filters are more expensive up front, but will generally last longer. While the initial investment could be quite high (depending on how many you need, the long term investment will save you a little bit of money.

The other factor to consider is the maintenance. With a disposable filter, you simply replace it with a new one. A washable filter will take time to clean, dry, and reuse. While it won’t take away your dinner plans, it is another chore that needs to be done.

One isn’t better than the other in terms of performance, only in personal preference. For those looking to lower their carbon footprint or reduce waste for the planet, a reusable filter is a good start. For convenience and affordability, disposable filters are the go-to option.

How to Change Your AC Air Filter

Once you locate the filter grate that houses the filter, changing it out is simple. Open the grating (usually a few push or pull tabs or even a set screw to remove) pull out the old filter and install the new one.

You should make sure the arrow on the filter frame points towards the HVAC system and not into the room. If you need more guidance on replacing your air conditioner filter, check out this short video.

Frequently Asked Questions

Have a question about air conditioner filters? We have the answers for you here.

What happens if the air filter is installed backwards?

Filters have a porous and non-porous side. You should take care to install so that the porous side faces the furnace or AC. Each filter will have a directional arrow for the airflow. Point the arrow toward the blower. If it is installed backward, the fan will have to work harder to create airflow which will, in turn, raise your energy costs and make the system more inefficient.

Where is the air filter in my AC unit located?

Air filter locations will vary from home to home. You should look for an air inlet grate in your walls or ceilings. In most cases, the grate will be near the furnace or AC itself. For a closet system, the grate is usually on the wall about knee-high. For attic installed systems the grate is generally in the ceiling in a hallway or bedroom.

Are there drawbacks to using AC filters with activated carbon?

The main drawbacks to activated carbon are replacement time and costs as well as the inability to filter some materials. Activated carbon filters don’t show signs of debris collection, so you have to keep track of installation date and replace based on the manufacturer’s suggestion. Carbon filters will not collect pollutants such as smoke, smog, pollen, or some other in-home air-borne allergens, which may be a concern for some homeowners.

installing filtrete filterHow often should I change my AC air filter?

The time frame to change your air filter is determined by the type and style of the filter itself. Most disposable filters will range from 30 to 90 days. Washable filters are generally in need of a clean after 30 days and should be replaced every six months to a year.

How much does it cost to get my AC serviced?

While we won’t be able to tell you exactly how much an AC service repair cost will be, the national average, as reported by Home Advisor, is about $356. The overall price is based on the type of service needed, the amount for labor, materials, and unexpected findings. You should get at least three quotes from licensed repair or service centers before making a decision.

How much does a replacement air filter normally cost?

Again, the exact cost will vary from location to location and will have a number of determining factors such as filter brand, type, replacement interval, and where you shop. For a disposable filter, the average cost is between $10 and $30 per filter for a standard 90-day, paper filter.

Where are some good places to get these filters?

You can get air filters at almost any store that has a home improvement section. This includes the Home Depot as well as local hardware stores. Shopping online, you can find great deals on air filters through Amazon, HVAC Direct, Filter Buy, and Walmart.com.

Conclusion

Whether you need to replace your home, RV, or automotive air filter, you have choices. The most cost-effective filter is a pleated, disposable filter such as the Filtrete model mentioned above. A high MERV/MPR/FPR rating is essential to capture pollutants and protect your HVAC system.

Spending a little more on the filter will save you money on energy costs and expensive repair bills later on down the road. Take the time now to make the right decision for your home air quality and pick the filter that will work best for your home, your personal needs, and your budget.

by jtanner jtanner No Comments

Buying Air Conditioner Parts: Central, Portable & Window AC

Air conditioning is one of the most taken for granted inventions of modern man. During the summer months when temperatures around the country often exceed 100 degrees, walking into a cool home is refreshing. What happens when you come home, and the air conditioner isn’t working? As humans, we go through a lot of emotions when something isn’t the way we expect it to be.

Once your emotions have settled and you have managed to cool yourself down a bit, it is time to think about calling a repairman or doing the work yourself. This article will cover the various types of air conditioners as well as how to troubleshoot the problem and buy air conditioner parts online.

How Air Conditioners Work

Air conditioners, for the most part, are simple machines. There are a lot of pieces that go into making them work, but the mechanics of it are simple. Power is supplied to the condenser which begins the air conditioning cycle. Inside the condenser, the refrigerant is condensed and pressurized, which causes it to become extremely cold and increases the pressure.

The high pressured refrigerant is sent through the copper tubing to the evaporator. The evaporator draws warm air into the system and blows it over the cold coils where the coolant is cycling through. This process causes the air to become chilled while heating and expanding the refrigerant.

Once the refrigerant has low pressure and a higher temperature, it is sent back to the compressor to start the cycle all over again. The result is air that is cooler than the ambient air of the home blown around to keep the rooms at a more comfortable temperature.

Types of Air Conditioning Units

While the process of cooling the air is the same for all air conditioning units, many brands have more (or less) parts added to the equation. Let’s examine the various types of air conditioning units.

Central AC Systems

A central AC is generally part of a heating, venting and air conditioning (HVAC) unit. However, some are cooling only, or heating and cooling. Likewise, there are also additional HVAC units, such as humidifiers, driers, and other components.

The central HVAC unit is a closet mounted unit with a large condenser and evaporator built into a cabinet or in the ceiling. The process of cooling the air mentioned above still applies. However, the cold air is then blown through ductwork hidden in the ceilings, floors, or walls and enters the various rooms of the home through vents.

These units will have a replaceable filter for the evaporator and a thermostat mounted on the wall to control the power, temperature and cooling modes.

Split AC systems & Ductless Mini-Split Systems

AC units in a rowA Split AC system is more commonly found in residential areas around the country. The main difference between a split system and a central AC system mentioned above is the location of the condenser.

A split system has the evaporator and blower mounted inside the home (in a closet or the attic, etc.) while the condenser sits outside the home.

The two are connected by the thermostat wires for power control, as well as high and low-pressure lines for the refrigerant to travel back and forth.

A Mini-Split system doesn’t use ductwork like the central and split AC systems. Instead, each room has a miniature evaporator and blower mounted that is usually controlled by a remote instead of a centralized thermostat. A mini-split system is more expensive to set up initially but can save a lot of money in the long run by only cooling rooms you need to be cooled.

Window/Room AC Systems

Another popular type of AC system is the window unit. This is a room air conditioner that sits in a window (there are also through-the-wall units). These units are smaller (obviously) to fit in a window and can produce enough cold air to keep a single room cool.

The units themselves are more affordable than any of the previous systems. However, you will need a window or room unit in each room of the home, which can add up in total costs. The units also require a lot of electricity, and your monthly energy bill can see a steep increase during the warmer months.

Portable AC Systems

Like a window AC, a portable air conditioning system is designed to keep a small area or room cool. These all-in-one units still need to be near a window for the exhaust vent. However, they are all-inclusive, and most units are mounted on wheels for easy portability. You can move them from one room to the next, plug into an existing outlet and begin cooling a room right away.

The downside to these units is that they require a lot of power to cool a room larger than about 65 square feet. If you have a place without a window to vent out of, you shouldn’t use a portable AC system. The exhaust fumes will not only make the room stuffy, muggy, and difficult to breathe in but will counteract the cooling by releasing hot air back into the room.

RV AC Systems

If you own an RV chances are you have an air conditioning system already installed. There will be a thermostat on the wall and room temperature sensors throughout the rig. The main unit, though, is mounted on the top of the RV to save space inside.

Under the shell, you will find a unit similar to a window AC. The compressor, condenser, and evaporator are all included within the shell space. The system works in the same way as well. Once the air is cooled, it is pushed through the ventilation system to blow cold air into the RV.

Car AC Systems

A car or truck AC system is slightly different. Each part is separated and connected through high and low-pressure lines, much like a split AC system. However, all of the components are spread around the engine compartment or under the firewall.

The system uses the compressor to condense and liquidize the refrigerant where it is sent through copper tubing to be cooled. As the cold refrigerant chills the coils in the evaporator, the air is drawn through the coils by the cabin blower and pushed out the vents into the cabin area of the car.

Signs That Your AC Needs Repair

Besides walking into a warm home, there are other signs your air conditioner may be going out. Let’s take a look at the most common tell-tale signs.

Warm Air

When the AC kicks on, you should be able to feel cool air coming from the vents. If the air coming out isn’t cold, there may be something wrong with your air unit. This can be a simple fix such as replacing the filter or something more complicated like a burnt-out capacitor on the condenser unit.

Insufficient Airflow

If the airflow coming from the vents or the AC unit (for portable or window systems) is low but cool, you could have a clog somewhere. The most likely culprit is the filter, but don’t neglect to check the ductwork or the evaporator blower motor.

Frequent Cycles

Another big sign is that the AC system appears to be working right, and the air is cool. However, the system itself comes on and off more frequently than it used to. In most cases, a faulty thermostat is to blame. However, it can also be a problem with the blower motor or the wiring to the evaporator unit.

High Humidity

High humidity levels are an indication that there is something wrong with the evaporator. Generally, the evaporator easily removes excess moisture from the air and coils. However, if the system is overworked, the temperature can drop below the dew point, causing excess condensation. This excess then gets moved around the home, creating a humid atmosphere.

The first thing to check for is open doors or windows. If you run the AC with the house opened up, the temperature will never reach the setpoint, and the system will continue to run, falling below the dew point. Other causes can be a clogged drain, dirty air filter or inefficient blower motor.

Water Leaks

A split system will have leaks from the evaporator unit and are mostly noticed when the system shuts off. If the drain is clogged the water build-up in the drip tray will be lifted by the blower motor. When the system shuts off, gravity brings the water down, and it escapes from access panels and other areas.

If you notice the condenser area is wet, this is generally a sign of freezing pipes and is the result of the condenser not working properly, or there isn’t enough refrigerant in the system.

Bad Odors

In most cases, you will notice a moldy or musty odor when the system isn’t running, or just after it kicks on. If this happens, the culprit is generally a mixture of dirty ducting, a clogged filter and excess moisture build-up. Combined, the ducting, filter and blower motor can begin to attract and grow mold spores.

When the system shuts off, the warmer air in the ducts will begin to permeate the odor. If the symptoms are more internal, you will notice the smell as soon as the air kicks on, and the airflow travels through the vents until the temperature of the air drops enough to cover the odor.

AC Replacement Parts

portable ac repairThere are a lot of cases where the homeowner can test and replace AC parts themselves. However, it should be noted that most residential and commercial air systems run on a direct-connect 220v electrical supply. Care should be taken to disable power before removing or testing parts.

You should also note that removing or adding refrigerant to an air conditioner system takes special tools and knowledge and must be done by a trained professional.

In most states, it is illegal to purchase refrigerant without a license or expel any refrigerant at all. This can lead to a fine of up to $10,000. If you suspect the problem lies in the refrigerant, it is best to call a professional for service or diagnosis.

Evaporator

The evaporator brings in the high-pressure liquid refrigerant and pushes it through the cooling coils where the air that passes through is chilled. The process of this heat exchange causes the refrigerant to heat up quickly and expand into a vapor. The pressure of the liquid is reduced, and the evaporator sends the low-pressure vapor back to the compressor to repeat the cycle.

Blower

Inside the evaporator unit, you will find the blower. This is generally a cage or hamster wheel style fan. The primary job of the blower is to pull warm air in and through the coils and then push, or blow, the cold air through the ductwork and out of the vents.

Expansion Valve

The expansion valve is part of the condenser unit, and it where the flow control of the refrigerant takes place. The valve regulates the flow from the condenser to the evaporator to keep the pressure of the refrigerant at a constant level.

Thermostat

cool imageThe thermostat is usually mounted on the wall in a centralized location. In residential areas, this is a hallway or a main room of the house.

The thermostat is where you set the preferred temperature, and when the ambient temperature of the home is higher than the set temp, the AC will kick on. When the house is cooled to the set temp, the AC will kick-off.

There are analog and digital thermostats with varying degrees of control options and features. In cars, there isn’t a thermostat. Instead, you turn the AC on or off manually, though you can select the blower speed.

Filters

Filters are essential for keeping the AC clean from debris and dust build-up. A clogged filter can lead to an overheated or overworked AC system as well as being the first step to a host of known AC issues.

Window and portable units use a filter screen that can be washed and replaced. Residential and commercial systems use a replaceable fiber filter that should be replaced every 30 to 90 days. For automotive systems, there is a cabin filter that should be replaced once a year (or more in hotter climates).

Belts

Belts are less common in window, portable, and residential units. However, they are a crucial part of automotive ACs. The belt drives the AC fan, compressor, and clutch and without the belt, the AC system won’t run at all.

If your car AC is acting up or not pushing any air, the first thing you should check is the belt. In modern cars, there is a single belt that is responsible for more than just the AC. If this belt breaks, your entire vehicle will have problems running, not only the AC.

Fan

All AC units will have a fan of some sort to remove the hot air from the compressor. In split units, this is a large fan affixed to the top of the housing on the outdoor unit. In window and portable units, the fan is a hamster-wheel style fan that circulates the air towards the rear of the machines.

If the fan motor goes out, the compressor can overheat, causing the system to shut down (most have a cut-off switch to prevent damage).

Refrigerant Gas/Freon

All air conditioning systems need a refrigerant to cool the air. Before 2003 Freon was used (labeled as R22 or R12 for home and automotive applications). The release of Freon, a CFC, is known to promote the depletion of the ozone layer and is being phased out. R22 and R12 are no longer being manufactured, and the supply already made is being sold at very high prices.

Newer systems use R-410a (for homes) and R-134a (for automotive applications.). These refrigerants are non-Freon and do not contain CFCs. They are considered safer for the environment and are now the primary refrigerants used in all systems.

The job of the refrigerant is to be pressurized and heated to allow the heat transfer of the air being blown over the coils. A small amount of lubrication oil is mixed in with all refrigerants which act to keep the internal parts lubricated and functioning properly.

Capacitor

The capacitor is mounted in the access panel of your condensing unit (the large box outside your home). This small cylinder is connected to the thermostat and from there to the compressor, fan, and even the evaporator and blower motor inside. When the thermostat tells the system, it is time to turn on (or off) the capacitor acts like a jumper cable, sending an electrical current to start the system.

Condenser & Condenser Coil

The condenser and condenser coil take the compressed refrigerant and cool it down before it can move to the evaporator. The process is quick since the vapor is at a high agitation state from being compressed. This is where you will find the expansion valve, too. Mixed within the cooling coils before the line goes to the evaporator.

Air Compressor

hot and cold imageThe air compressor is the heart of the entire unit. Its job is to take in the low-pressure vapor refrigerant and compress it into a high-pressure vapor.

The compressor then pumps the hot vapor through the coils, which cause it to become cold. It is then sent on as a cold liquid to an expansion valve.

All air conditioning systems have a compressor of some type, regardless of application. Servicing a compressor should be done by a professional because it deals with the transfer of refrigerant.

Remote Control & Controller System

On window and portable AC units (and some smart home digital thermostats), you control the system with a remote control. These remote controls allow you to set the temperature, turn the unit on or off and adjust airflow, speed, and power settings.

Fan Motor

For most systems int eh home there are two fan motors. The first is the motor for the fan on the condenser unit outside. The second is the motor that controls the blower fans in the evaporator unit.

As with all electrical components, the motors will eventually burn out and need to be replaced. This is something that most homeowners can do with simple tools. As long as care is taken to disable power to the motors and other components before removal, the job shouldn’t take longer than an hour (depending on the rust or wear on the mounting bolts.).

Adjustable Louvers

Car AC units, as well as window and portable ACs, will have adjustable louvers. These are the small blades on the vents that allow you to control airflow direction. Over time, with repeated adjustments, the louvers can break or come off. This is the easiest part of a system to replace, although finding the correct replacement louvers can take a bit of research.

Why are Car AC Parts different?

An automotive air conditioning system is slightly different in the functionality of the parts. While both home and car ACs are designed to serve the same purpose, they do go about it in different ways.

A car AC is smaller, and the parts are spread further apart in most cases. The main difference is that a thermostat doesn’t control a car AC. Instead, it is either on (clutch engaged) or off (clutch disengaged). However, even with the compressor clutch disengaged, the system is still running.

The system runs when the car is on because it is belt driven and the belts spin when the engine is running. The compressor clutch is the key element that turns the system on to blow cold air through the cabin or lets the refrigerant cycle around until it is needed. Home and commercial ACs don’t have a clutch, nor are they belt-driven. Everything on these systems is electrical.

Common Brands of AC Units

Let’s take a look at some of the most popular brands of the different air conditioning systems we have covered in this article. We will also point out what to watch for when purchasing a specific brand or style.

Central & Split System Comment
Coleman Coleman is a name more associated with camping gear. However, they produce a line of central and split system units. They also have an unrivaled warranty. This includes a lifetime warranty on the compressor. The main issue here is finding parts, which can be challenging to obtain and costly to replace.
LG LG makes a lot of electronics and home accessories, including split system ACs. Known for reliability and accessibility, the LG systems are efficient, quiet, and cost-effective. Their downside is in the warranty, which is limited and difficult to claim against. If the unit does break down, prepare to be on your own.
Hisense Hisense is relatively new to the American market and is known for making more-than-affordable appliances. Their systems will be cheaper to purchase and install, but their dependability leaves a bit to be desired.
Lennox Lennox is a name that has been around for years and conjures images of an older man in overalls. Reliable, warrantied, and dependable central and split AC units have been the backbone of this company for decades. One main issue is the cost-effectiveness. Relying on brand recognition, they aren’t about to lower prices to be more competitive.
Carrier Carrier has long been used for commercial applications and in business that requires large, dependable units. For the residential side, the initial installation costs may be more than you want to pay, but you won’t have to worry about the unit breaking down for at least 20 years.
Rheem Rheem entered the commercial market long before they ventured into the residential market, and their prices reflect that. While their home units are dependable and long-lasting, you will pay less with almost every other name brand unit. Not many will last longer though, but the trade-off isn’t worth it to some.
Ruud Rudd is about as middle of the road as you can get. They aren’t fancy, but they aren’t bottom of the barrel, either. Their cost, warranties, and dependability all fall in the “about-average” section of the market.
Goodman Goodman is a name you can trust when it comes to split ACs. These units are cost-effective and trusted by many multi-home complexes around the country. They offer unrivaled attention to detail and parts are available through virtually any online retailer, making them accessible as well as affordable. Just don’t expect too much from the limited warranties on the parts. You will be talked out of a claim if you allow it.
Amana Amana is better at small appliance cooling than home cooling, but that doesn’t stop them from trying. While they make a better refrigerator than AC, their split systems and central systems are cost-effective and will save you money on your energy bill – while they are running, at least.
Trane Nothing runs like a Trane is the catchphrase that has entered our homes for decades, and we know the company to be reliable and durable. Parts for these units must be exact, though, and anything other than the Trane name going in the units will void the warranty.
American Standard American Standard is one of the most cost-effective, name brands available today. American Standard is readily available at most home improvement stores, and their parts are affordable. However, with cheaper parts, you will be doing more replacements for worn pieces than you will with other, more expensive units.
Daikin The Japanese maker, Daikin, has an affordable answer to your home’s cooling systems. Their main drawback is in locating replacement parts. It seems they have gone out of their way to be different enough to be almost exclusive. Finding parts is better done online than in person, just make sure you have the right model numbers to ensure a proper fit.
Window AC Comment
LG When it comes to a window or through-the-wall units, LG is king. The features and prices make the units efficient, energy-saving, and affordable. You won’t find a selection that offers more anywhere else. Expect to pay for that selection, though.
Haier Haier is eye-catching because of its low price tag. While the units are energy-efficient, the catch is they are only cost-effective on low settings, which won’t’ cool off a walk-in closet. If you want long-term savings, Haier isn’t the right choice. However, if you need a temporary fix or are just looking to cool off a single room for a short time, their price is unmatched.
Arctic King Arctic King was once a powerhouse in the window unit market. Balancing reliability and cost, the company once ruled the market as their moniker suggests. In the last 10 years, though, they have sacrificed production by using cheaper parts. While they will cool your home, you will need service more often.
GE GE has a thumb in every pie, and the window air conditioning market is one such pie. GE is as reliable as they are well known, and the AC industry side of the company gives you exactly what they say. The warranty could be better, though, and many find that having to go through Sears to make a claim can be a problem at times.
Frigidaire Frigidaire, like Amana, uses their technology to enter new markets. When they began producing window units, the product was sub-par. Nowadays, they are more reliable and energy-efficient, but for the price, you can do better with less long-term worry.
Portable AC Comment
LG Unlike the window units, the LG portable units are not as reliable. The machines are loud and require more maintenance during setup than should be allowed. However, once set up, connected and the exhaust and drain tubes are correctly affixed, the units will cool an entire room quickly.
GE GE portable units aren’t as reliable as the rest of the GE line. You will go through a few warranty claims (as reported by many owners), and GE customer service isn’t up to par. However, with the bad out of the way, for a temporary unit that you want to use sparingly or only for a couple of seasons, the price point is low, and the units will cool a room efficiently.
Dometic Known primarily for their RV air conditioners, the Dometic portable units are surprisingly good. They come with feature sets typically only found in window units and are durable. On top of that, customer service is quick to respond and overly helpful.
Friedrich Friedrich is not quite a household name, but it should be. The portable AC units are durable, reliable, and cost-effective. They will zap more energy than other models on this list, but they withstand a lot more, too. One major issue is the reservoir shutoff, which kills the nit if the drip tray becomes full. This happens more than it should for a unit designed to evaporate the tray regularly.
DeLonghi DeLonghi also owns the Braun and Kenwood, if you aren’t familiar with the Italian name. The units do cool efficiently. However, they are loud and cumbersome. If you plan to sleep with the unit in the bedroom, plan on a restless night. If you have hardwood flooring, the wheels can cause groves or wear marks because of the weight the wheels have to bear.
RV AC Brands Comment
Coleman & Coleman RV Coleman and specifically the Coleman RV branch makes a reliable and cost-effective AC unit for your motor home. The sensors are a bit confusing and can be triggered by the smallest drafts. However, with proper placement and planning, this can be avoided.
Dometic Dometic RV air conditioners are the benchmark of the market. There is little bad to say about these machines except that a new install can be costly. However, once installed, they are virtually worry-free and easy to maintain.

Cleaning Your AC

Regular maintenance of your AC unit is paramount if you want it to run efficiently and cool the home in a timely manner. There are a few things you can do to keep the unit working correctly.

Change the filter out promptly. Each filter will have a life span printed on the packaging. Usually, these filters will last between 30 and 90 days. You should change the filter before this time is up and not run the air conditioner without a filter.

Cleaning the coils yearly will help prevent build-up, promote airflow, and keep the drains clean. The evaporator coils will get caked with dirt and dust from use. This is normal. Opening the access panel will allow you to get to the coils. A coil cleaning solution and coil brush should be used. The fins on the coils and evaporator should remain straight. Any bends will block airflow.

On the condenser unit, you can clean off the vents with a pressure washer or garden hose. If the debris has accumulated and begun to cling to the vents and coils, you can use a propane torch to burn them clean. Care should be taken not to burn the wiring or apply direct heat to any portion of the unit except the vents and coils.

DIY Air Conditioning Repair

There are two portions of the air conditioner that can cause problems, refrigerant leaks, and electrical components. For refrigerant leaks, the culprit usually responsible will be the fill valve cores (Schrader valve). Over time the rubber o-rings on the cores will go bad, allowing small amounts of refrigerant to escape.

However, it takes a specialized tool and knowledge of the system to replace a valve core without leaking refrigerant (which is illegal). While you can purchase the core replacement tool, when the refrigerant system is involved, it is best to call in a licensed professional.

For the electrical system, the most common failed components are the capacitor, contactor, and fan motors. The homeowner can replace each of these parts without the need to contact a professional. However, you need to first shut off the power supply to the condenser unit and short the terminals on the capacitor (it stores a small amount of power).

Because the capacitor and contactor are explicitly wired, it is essential to label the wires before removing them and reattach them in the correct spots. The fan motors (condenser unit or blower motor) can be removed from the units and replaced on a workbench or in a garage. Make sure the motors are the correct size, power, and rotational direction before purchasing a new one.

Buying Online vs. a Store Near Me

Depending on the part and what you need, it may be more beneficial to shop at a local store. Other times it can be quicker to shop online. How can you tell which to do? In short, both methods will eventually get you what you need. However, there are certain instances when online shopping will be more beneficial.

If you know the part number, you can quickly get quotes from various online vendors. Of our favorites, Amazon.com and HVACpartsUSA.com are among the most reliable. However, they often aren’t the cheapest. For specialized parts, you can shop online at Sylvane or even HVACdirect. Both will offer competitive prices on older models and specific parts for your systems.

Finally, we trust HeatandCool.com for their reliable service, fast shipping, and easy to talk to experts.

You may want to shop locally though, and there are a couple of reasons that make this the smarter choice. First is timing. If you come home and your AC is broken, you will need the fix as soon as possible. You may not have the time to wait on shipping and will spend whatever it costs to get the part right now. In this case, a local HVAC supplier will be your best bet.

The second reason for shopping local is when you can’t identify the part number. Perhaps age has removed the number, or your OEM part doesn’t have a part number stamped on it. When this happens, you can take the piece to a local shop and compare it to those on the shelf. Making sure the connections, mounting holes, and sizes are all a perfect match.

Frequently Asked Questions

Now we will answer some of the more common questions about air conditioning units.

Which gas is used in ACs?

For most residential and commercial air conditioners, the refrigerant used is either R22 or R410a. For automotive ACs the refrigerant is either R12, R134a or the newer R1234yf types. You should note that both R12 and R22 are CFC refrigerants (commonly called Freon) and are being outlawed.

What is the difference between R-22 and R-410a refrigerants?

R22, also called Freon, is a CFC based refrigerant that is known to promote ozone depletion. R134a, known as Puron, does not contain CFCs and is safer for the environment. Both liquids become gases under pressure and will heat up under pressure. This is what makes the system cool the air as the heat transfer of the gases causes a rapid temperature decline during a state change.

Where can I find the model and serial numbers of my AC unit?

For split AC systems commonly found in homes, the model and serial numbers will be found in the owner’s manual or on a sticker located on the condenser unit. This sticker is usually found on the access panel to the capacitor and contactor area.

How do I know the part number of an AC replacement part?

Most AC components will have a model number stamped into the framework of the unit. For example, the fan motors will have a plate where the information is stamped. The compressors will have a stamp located on the pump housing or sometimes as a plastic tag attached to the mounting bolt holes. If you are in doubt, the manufacturer will have OEM part numbers for your specific unit listed on their websites or in the owner’s manual.

Are air conditioner parts covered with a warranty?

The exact parts covered in a warranty will vary by manufacturer. In general, larger parts such as the blower, compressor, lines, housings, and electrical components are included. Replaceable parts such as the capacitors or contactors will not, usually, be covered.

How often should AC coils be cleaned?

It is advised to clean the AC coils once per season before putting the AC to use, or every six months. If you find that the filter has been perforated an extra cleaning may be needed during the season.

How many parts does an AC have?

The number of parts will change with each manufacturer. However, the primary components won’t change. The AC system will have at least five elements: compressor, evaporator, fan, coils, and electrical parts (contactor, capacitor, etc.). Depending on how the items are grouped, the size of the unit and if it has any other purposes (such as heating), the number of parts will increase.

Conclusion

As you can see, having an air conditioning system is almost a necessity. In the late spring and summer months, central air or split system air is crucial. Depending on where you live, you may get away with a single room or window air conditioner or even a portable AC.

With ownership comes responsibility, though. To help keep the energy costs down, cool your home or room efficiently, and keep the unit working correctly, you will need to do some maintenance. When the time comes, knowing what parts to replace and when it is better to call a professional will save you a lot of headaches.

Shopping online may be the best option and is undoubtedly the fastest. You can get multiple quotes for your parts in a short amount of time, without having to travel all over town. When time is an issue because your home isn’t being cooled, every minute helps.

by jtanner jtanner No Comments

Analog vs Digital Thermostats Compared

Best Analog Thermostat

White-Rodgers Emerson 1F56N-444
White-Rodgers Emerson 1F56N-444

Best Digital Thermostat

Nest Learning Thermostat – 2nd Generation T200577
Nest Learning Thermostat (2nd Gen)

If you are looking for a way to save money around the house, or lower your carbon footprint, you may want to consider changing out your thermostat. With the technological advancements in home heating and cooling the analog vs. digital thermostats battle is shaping up to favor the digital methods.

There are several advantages of digital thermostats and few disadvantages. This article will examine the analog and digital thermostat types to help you decide if it is time to make a switch.

Types of Thermostats

There are two main types of thermostatic controls; line voltage, and low voltage. Each one can be controlled with either analog or digital thermostats. Here is the difference between the two types.

Line Voltage Systems

Line voltage systems are those that run boilers or furnaces. These systems only need the electrical jump-start to get going then use other means to maintain their performance. The thermostats are generally the same, though, and the systems tend to be in the 120-volt to 240-volt range.

Analog thermostats use mercury along with the internal thermometer to tell the system when to shut on or off. They can also use mechanical switches instead of mercury, which is a conscious environmental mechanism but isn’t entirely as accurate.

Digital thermostats for line voltage systems, like their low voltage counterparts, come in both programmable and manual types. Either way, you go there will be a digital interface for you to control (or program and forget) based on the temperature, time of day or season.

Low Voltage Systems

Low voltage systems are those that run on electricity, and the majority of homes and business will run these types of systems. Because they run on standard 24 volt (VAC) electrical systems, a heating and air conditioning system don’t use as much electricity as the line voltage systems, keeping your energy bill lower.

Analog thermostats plug into the system and mount on the wall allowing you to set the mode (heating, cooling or fan), and slide a dial to the desired temperature range. These thermostats have a thermometer built in to gauge the ambient temperature around the thermostat and turn the system on or off accordingly.

Digital thermostats also mount on the wall and plug into the system. You can use the touch-screen or other control methods to set the exact temperature, and the system will shut on or off according to the temperature reading of the thermostat.

How Thermostats Work

The thermostat on your wall has one of the most crucial HVAC jobs around, yet it is a simple device. So how do analog and digital thermostats work? The devil is in the details.

Analog Thermostats

Analog thermostats use a bi-metal strip or a coil that is connected to the thermometer. When the temperature goes up, the metal expands, when the temperature drops, the metal constricts. This movement is what causes the contacts to connect.

Generally, the contacts are connected to a mercury bulb. The mercury acts as the conductive material to complete the circuit. On one side, the heater connections are waiting for the mercury. When the temperature drops the bi-metal causes the bulb to tilt towards the heating contacts where the mercury completes the circuit, and the heater comes on. The opposite tilt will result in the cooling system to come on.

Digital Thermostats

Smart Home ThermostatDigital thermostats don’t use mercury or glass bubbles. Instead, they use a little item called a thermistor. This device measures the temperature from the thermometer (or sensors) which is read and evaluated by the computer chip.

After a few algorithms, the temperature is displayed as a number on the screen. As the temperature increases or decreases, the cooling or heating portions of the system will come on (or shut off).

Everything is done using computer-based algorithms for a more accurate reading and control of the system, which will save you money on your energy bill in the long run.

Are You Scared of Going Digital?

Digital thermostats are a better option for most people. If you are upgrading your system, want more control over your heating and cooling or are just looking for accuracy and energy cost savings, digital wins every time.

The main deterrent, when speaking to people about digital thermostats, is installation and upfront costs. However, if you can turn a screwdriver, you can install a digital thermostat. If you can play Candy Crush on your smartphone, you can program a digital thermostat, too.

As for the cost, a digital thermostat is more expensive than a traditional analog unit, however, within the first year of running your HVAC system, the money you save on your energy bill will more than make up for the cost variance.

Home Thermostat Buying Guide

What should you look for when making your final purchase decision? We give you the important things to think about right here. Read below to find out more.

Control Voltage Type

portable thermostatAs we described above, the type of connections will matter the most. If you have an existing system and don’t know which model you have, it is easy to find out. However, for most of you, the thermostat and HVAC system will be low voltage.

For a quick check, see if your thermostat has an off position. If it does, it is low voltage. Line voltages don’t generally have an “Off” setting, just a “lowest setting” position. If you are still unsure, check your owner’s manual or with the manufacturer to be sure.

Central Heating System

For a heat-only system such as a furnace, boiler, or electrical unit, you will most likely need a line voltage thermostat. The best thing to do is to note which thermostat is already there and replace it with the same type. If you are looking to upgrade to a digital thermostat from an analog one, double-check that the new thermostat is designed for your system.

Thermostat Type Preference

For home and business use, the question comes down to your preference. Some people like the ease of use of the analog system or don’t have the desire for a smart-home integrated thermostat. On the other hand, if you are looking for a digital upgrade, that is your choice.

While no one can decide for you, it is best to go into the shopping experience knowing which style you are after. It will narrow down your choices and make finding the perfect thermostat much easier.

Accuracy & Energy Savings

When speaking of accuracy, you will want the heating or cooling to kick on at a specific temperature. All thermostats will have a variance of a few degrees.

This variance means that if you set the system to come on at 75 degrees, it may actually be 72 or 78 degrees when the system kicks on. Analog thermostats have a much higher variance than digital ones, making digital thermostats much more accurate.

Because of the accuracy, digital thermostats run systems more efficiently, which saves you money. Your energy costs will level out and, in most cases, will drop offering you substantial savings over the life of the thermostat.

Ease of Use and Installation

Thermostat on wallUnless your digital thermostat is a smart thermostat (such as a Nest), the installation for analog and digital thermostats are the same. You will put the wires in their correct slots and power on the unit.

If you can turn a screwdriver, you can install either a digital or analog thermostat with the same amount of effort. The difference will come in programming.

Analog thermostats aren’t programmable, so once you power the system and replace the faceplate, your job is done. However, for a programmable digital unit, You will have to set things like the date, time, system information, and other settings. It isn’t tricky, but it can be time-consuming.

Warranty

Depending on the type of thermostat, manufacturer, and features, thermostats will come with a warranty. How long the warranty is will vary. If you are purchasing a more expensive thermostat you need to check on the warranty, return period, and how to make a claim before making your final purchase.

In the event you need the warranty, it is better to know at the start what materials, proof of purchases and costs for shipping you are responsible for.

Analog Thermostats Reviewed

1. White-Rodgers Emerson 1F56N-444

White-Rodgers Emerson thermostats are installed in homes across the country. For over 50 years their thermostats have made their way into our homes and for a good reason — dependable, reliable service at an affordable price. The 1F56N-444 model is an update to the thermostats used in the past and has a similar size footprint to avoid painting or wall patches for install.

The bi-metal strip and mechanical gauges make the system more economical and efficient to keep your home at the correct temperature year-round. This analog thermostat is white to blend into the wall and has a simple interface to select mode, temperature, and fan controls.

A 3-year warranty protects your investment against defects in operations and craftsmanship. The low cost and simple installation will have you up and running in less than 10 minutes.

2. Suburban 232229 161154

Best Analog Thermostat for Heating Only

The low voltage heat-only thermostat from Suburban is one of the easiest installation thermostats around. Explicitly designed for heat-only systems, furnaces, and boilers, you can replace your existing thermostat within 10 minutes.

The thermostat features an off toggle (lowest setting plus one) and an easy to read temperature selector. Once installed, the thermostat will handle the rest. The low-cost and straightforward to install features are just part of the allure to the Suburban 232229. The other draws are the dependable bi-metal sensor, reliable furnace controls, and wall-blending color.

3. Dometic 3106995.032 RV Thermostat

The Dometic analog thermostat brings HVAC controls to your RV and is one of the most trusted brands around. The Dometic 3106995.032 RV Thermostat is a specific replacement only model. To use this particular model number, your distribution box model number must be 3107541.009. This model is also design specific, meaning it won’t work with heat strips or heat pumps.

You can contact Dometic to find the specific replacement model for you if this one is not it (toll-free at 1-800-544-4881). Regardless of the actual part number, the HVAC controls of Dometic thermostats keep your RV at the ideal temperature during any season. With a temperature range of 32 to 90 degrees Fahrenheit (0 to 32 Celsius), you will have no problem finding the perfect temperature regardless of where you are.

Digital Thermostats We Like

1. Nest Learning Thermostat, 2nd Generation

Best Digital Thermostat For Central AC

When it comes to smart thermostats, the title of “best” can be entirely subjective. With so many different features to compare, it can be hard to tell which one is best for you. However, with models like Honeywell and Ecobee competing for a spot in the market, Nest still stands tall.

It has all of the features you need, some you didn’t even know you needed (like ambient temperature adjustments, room sensors, etc.), and others that you just want. With Alexa voice controls, mobile app controls, and a sleek user interface that looks good on your wall, the Nest Learning Thermostat Gen 2 is a cut above.

The best part is that once the thermostat is installed in your home, it will begin learning your patterns and automatically adjusting your home’s temperature based on your habits. In the first year alone you can save over 30 percent on your energy bill.

2. Honeywell RTH2300B1012

Best Programmable Digital Thermostat For Heating

If you have a heat-only system, you can upgrade to a digital thermostat, too. The Honeywell digital thermostat is ideal for homes with or without central air conditioning. You will find that the Honeywell is simple to install and takes virtually no time to program.

The actual controls are simple and straightforward, allowing you to get back to your day without worrying if you have a setting wrong on your heating system. The overall cost savings make the few extra dollars upfront even more worthwhile.

Need a Non-Programmable Thermostat for heat only? This similar Honeywell Pro Model is a great choice.

3. Coleman Airxcel

The Coleman Airxcel Machine thermostat is designed to replace almost every RV thermostat from the last ten years. It uses a simple installation process (only two screws) and runs all 12-volt low voltage systems. The exception here is that it is not designed for heat pumps or zone controls.

If your RV needs to have the thermostat replaced, upgrading to the Coleman digital thermostat is a simple choice – do it. Even if your existing system uses the dual-red wire power system, this thermostat can accommodate. Cut down your heating and cooling costs starting today with this intuitive digital thermostat.

Need a more control in your RV Thermostat? This similar Coleman Model is a great choice

Thermostats: System Zoning

temperature thermostatYour home most likely has a single zone. This means you have one thermostat to control the temperature of the entire house. While this is convenient, it is also wasteful of energy resources. A zoned system uses multiple thermostats set up in zones.

The thermostats connect to a zone control panel which will activate dampers installed in the HVAC ductwork. By controlling each zone independently, you get the right temperature for the room or rooms you are occupying. The cost savings then, are found when you don’t heat or cool rooms that don’t need it, like the unused guest room, for example.

How to Install Thermostats

Honeywell thermostat wallIn over 90 percent of the cases, installing a digital and analog thermostat are going to be the same. Each manufacturer will have a slightly different installation procedure, so check the owner’s manual before you begin.

Each of the wires in your current system should be color-coded. However, the colors can fade, get caked with dust, and it may become difficult to tell the difference between blue and green, or orange and red.

It is advised that you mark each wire with a label for the port that it is removed from when taking apart your old thermostat.

From there, you will screw the mounting plate in place and pull the wires through. Following the labels, replace the wires in the correct ports and press the faceplate into position. When done correctly, the system should come on when you turn the power on and select a heating or cooling mode.

Switching from Analog to Digital

In virtually every case of replacing an analog thermostat with a digital one, there is very little you need to do differently. The only difference comes in the size of the thermostat. There may need to be some patchwork done to the wall to cover a larger hole or to paint the wall before the new installation.

Aside from these situations, installing a digital thermostat is identical to installing an analog one, which decides to upgrade to a more efficient digital thermostat even easier.

Conclusion

Replacing your thermostat shouldn’t be a chore, and it doesn’t have to be. While you can replace your thermostat with an exact exchange, it may be beneficial to upgrade to a digital thermostat.

The downside to the digital upgrade is the initial cost. However, with careful planning, you can offset the cost difference in just a few months. The amount of energy savings a digital thermostat provide compared to an analog thermostat are incredible.

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