There is a lot of confusion when it comes to the types of home climate control systems, how they perform, and which is the best option for your home. Two of the more popular types are explained and compared in this forced air vs. central air review.
We will outline what exactly forced air systems and central air systems are and compare them side by side to see if one type is best suited for you and your home over the other.
Forced Air Vs. Central Air: Which Is The Better Choice?
There are a lot of misconceptions between the two terms “forced air” and “central air” systems. We will be spending some time clearing that up in the sections further below. For right now, though, we will tell you that when most people speak of forced air systems, they are referring to a heating unit. Likewise, when central air is mentioned, it typically refers to a cooling air system.
While this isn’t actually the case, it does offer some interesting comparison features and factors. So, before we dive into the clarification of these systems and what the terms actually mean, let’s look at them side by side on various decision-making situations.
Cooling / Heating Capacity
The cooling and heating capacity of these two systems will depend on the brand, model, size, and output of the unit installed. For an average residential home, a 2 to 2.5 ton central unit is usually needed. Heating systems will also vary based on connection types; oil, gas, electric, or other will all factor in the output capacities.
Because heat pumps, furnaces, oil heaters, and any other heating system that uses ducting to move the air to various rooms are all forced air systems. The heating capacity will depend on the system type you have installed.
Winner: Tie. Both types of systems’ capacities are wide-ranged and varied based on many factors.
Energy Efficiency Rating
The energy efficiency ratings are different based on the type of unit (heating or cooling). Cooling systems are rated using the Seasonal Energy Efficiency Ratio (SEER) rating. Heating systems use the Heating Seasonal Performance Factor (HSPF) rating. However, they both measure the same thing.
The ratios are derived from the wattage input needed to power the device compared to the BTU output of the device. The SEER rating is measured when the system is running on high during the summer months. HSPF, then, is measured when the heating system is running on high during the cooler winter months.
In both cases, a higher number will mean a more efficient system. For the cooling aspect, most modern devices range between 13 and 25 SEER. There are some exceptions, typically with higher SEER values, but the average is between 16 and 18 SEER overall.
For HSPF values, the range typically averages between 9 and 10 HSPF. Of course, some systems are much lower, and a few are much higher (some even reach up to 13 or 14 HSPF).
Winner: Tie. The output is determined by the capacity of the unit itself, not by the style of the system.
Initial Purchase Cost
The purchase cost will also be determined by the type, size, and style of system you install. A central air system is designed to cool the air in your home, while the furnace or heat pump using the ducting is designed to heat the home.
When looking at cost, one of the most significant determining factors will be the output size. Generally listed as BTUs, this size is determined by the square footage of the home and the climate of the region.
For a central air system, you are looking at an initial cost between $3,500 and $8,000 on average. Some systems are cheaper, down to about $1,200, and some can reach over $10,000 in costs.
For furnaces and heat pumps, the average cost also fluctuates. However, the average is much lower, with ranges between $2,000 and $5,500 being more common. A combined unit that does both heat and cooling is about the same as a central air unit and may be the best option.
Winner: Forced air heating systems are typically much cheaper than central air cooling systems.
HVAC Installation Cost
HVAC costs are not a one-size-fits-all type of thing. Instead, multiple factors go into the final numbers, more so than in almost any other field. For example, labor fees vary from region to region, even within a city or between contractors.
You also have to figure in the extra work, removal of the old system, ductwork installation or repairs, and any hidden fees such as lead paint or asbestos removal. According to Modernize, the average US installation fees for central AC units range between $2,631 and $12,586.
One of the biggest factors, though, is the type of unit you are installing. A central AC unit, for example, will typically range between $3,500 and $7,600. However, a forced air furnace system can range between $1,500 and $6,500, with oil and gas models being the more expensive options.
Winner: Forced air furnaces typically (though not always) cost less than a central AC unit to install.
Forced air furnaces come in many fuel options, including oil, propane, natural gas, and electric. Obviously, the gas-powered models don’t use electricity and can save you money on that end. However, the gas supply or refills can get just as expensive as electricity.
For the electric models, though, the average residential usage will connect to a 220-volt breaker using 60 or 80 amps. While amount of electricity will vary by season, year and restrictions, you can count on about 20,000 watts of electric usage per hour.
Central air systems use a lot of electricity too. However, since they don’t have the heating elements like furnaces, they won’t use as much as a furnace. For an average residential install, the 220-volt system will use about 3000 watts per hour.
The trade-off, though, is that in warmer climates, the AC will run longer and use more electricity overall than a furnace. In the winter, it will be the opposite.
Winner: Central ACs will consume less electricity over a year than an electric forced air furnace.
Indoor Air Quality
Indoor air quality (IAQ) will come down to cleaning, testing, and filtration. The first step is to clean your home of dust, dirt, and debris. A good thorough clean is essential for all related components to function properly.
All forced air systems will have at least one filter along the airflow path at some point. Most units will use a single air filter at the main intake vent, and others will be in the unit housing itself. The higher the quality of filter you use, the better IAQ you will receive.
However, you must clean or change the filter regularly. Usually, the time of use is 30, 60, or 90 days. Having a clean home, clean ductwork, and a new filter will significantly increase your IAQ overall but has little to do with the actual system.
Unless that system has damage to the ducting, you shouldn’t have any problems. If air is getting in other areas, a central AC can drop the air quality. Furnaces can also introduce moisture into the system, which can create mildew and mold.
Winner: Tie. Both systems use closed air systems with proper filtration to help maintain indoor air quality.
Forced Air System: Overview & How it Works?
Forced air systems typically refer to heating sources such as furnaces. The whole truth, though, is much more simple. A forced air system can be an HVAC system that uses fans and motors to pull air in and move it through a series of ducting to individual rooms.
Brands, consumers, and even technicians usually say furnaces or forced air systems when talking about them. While interchangeable, though, your central air conditioner is also a forced air system. This is where the confusion lies.
A central air system is also typically meant for cooling but can include a heating element for central heating as well (more below). Because these two systems are interchangeable, it is important to keep in mind that furnaces, heat pumps, and central ACs are all forced air systems.
For our purposes, we will use the heating side of a forced air system to complete this review. A furnace pulls air into the heating chamber after it goes through a filter. The heated air is then moved through the ducting in the attic, ceiling, or even under the floors until it reaches a vent.
Each room will have a vent, and that room will receive hot air from the forced air system. If you do not wish to have a specific room heated, you only need to close or cover the vent.
Different Types of Forced Air
Forced air heating comes in various styles and types of heating sources. The styles refer to how the system is mounted and where it is located. For example, Upflow systems are installed in the basement and push the air up into the home. Downflow systems mount in the attic space and push air down into the house.
Finally, you have horizontal styles that are generally found on ground level in single-family homes or apartments. The fuel type, though, will be the main factor in which type you use. Let’s look at those more closely.
Arguably the most common form of furnace is a burned fuel furnaces. This refers to any heating system that burns a fuel source to produce the heat. You can find these in gas or propane in almost every region of the US.
However, it also includes other fuel sources like oil, coal, and wood. The principle behind all fuel sources is the same. A burner ignites, using the chosen fuel supply to create heat. That heat is transferred to the air inside the furnace and pushed through the ductwork with fans.
These systems are efficient, easy to use, and don’t require a lot (or any) electricity. The downside is that propane and natural gas prices fluctuate. Oil, coal, and wood can be difficult to find, and depending on how long your season is, you may need to buy several refills.
Electric furnaces aren’t as efficient in the long run as a natural gas or propane model, but for forced air heat, they are simple, economical, and perform well. Unlike a fuel-sourced furnace, electric forced air units have heating coils or elements.
As the electricity runs through the coils, they heat up, glowing red in the process. This produces heat that is transferred to the air as it is pulled over the coils. The hot air is then pushed, via fans, to the individual rooms through your ducting.
While the units can use a lot of electricity to maintain a temperature, they are fast and don’t run as long as other options. Your winter power bills, though, will see a spike compared to the more mild months.
Heat pumps come in many forms, and one of the largest growing groups is ductless mini splits. These are not forced air systems as there are no ducts to move the air. However, ducted mini-splits can replace current ducted systems, including furnaces and even air conditioners.
Electric heat pumps are highly efficient and can even have better cost savings than central air conditioners. These systems move heat rather than creating it, which means they use less energy to heat your space and can even install with your current system to use the ducting already in place.
Hydronic coil heating has a few names that all mean the same thing. You may know them as a hot water furnace or a water heater furnace. The mechanics are the same. The system uses water (hydro) or other liquid mediums to transfer heat to the air, which then moves to the home.
Large buildings use boilers to move and heat the water, but a residential home won’t need that big of a system. What you will need is essentially a large or oversized water heater. They are efficient because they don’t use a refillable fuel source like gas or wood.
Hydronic heating coils aren’t a stand-alone system, though, and will require compatible HVAC systems. Most major brands like Carrier, Trane, and others all have compatible systems. All you will need to add is a heating coil made for water and a pump to move the water inside the piping.
Pros & Cons of Forced Air Heating In Homes
Forced air heating has several good things going for it and, of course, there are some downsides. Let’s look at both sides of the coin, so you know what to expect.
What We Like
- Multiple fuel types to power the units
- Long warranties offered by most brands
- Low installation costs
- Simple operation with low upkeep
- More efficient the single room heaters
Things We Don’t
- Not the cleanest or most eco-friendly option
- Electric models can become expensive to operate
- Higher risks and dangers associated with use.
- Mold and mildew are big concerns.
Central Air System: Overview & How it Works?
Central air systems can be connected to an evaporator unit that includes heating elements. This makes it a ombined forced air system for both heating and cooling.
For the cooling side, though, and the basis of this review, central units are common and easy to operate. The condenser unit is the outside unit that houses the compressor and condenser coils. Inside (usually in the attic or over the bathroom) is the evaporator unit that houses the evaporator coils and fans.
When the system is running, refrigerant moves from the compressor to the evaporator coils. The pressure exchange causes the heat in the air to absorb into the refrigerant, leaving the air cold. The cold air is pushed through the ducting to the rooms in the home.
Meanwhile, the not heated refrigerant moves outside to the condenser unit, where the heat is removed outside and re-pressurized in the compressor, where the cycle repeats and continues.
On models with heating elements, the system runs without the condenser unit or need for the refrigerant flow, and the air is moved through the evaporator unit, through the heater coils, and out into the home.
Pros & Cons of Central Air
Like every other product, central air conditioners have good and negative aspects. Let’s take a look at the good and the bad sides so you can make a well-informed decision.
What We Like
- Simple design with high efficiency possible
- Standard installation costs
- Multiple sizes and capacities available
- Various filtration levels for better IAQ
- Smart home compatible
Things We Don’t
- Must have ducting for airflow
- Can be expensive to run year-round
- Some regions require minimum SEER ratings
Can You Change Forced Air to Central Air?
If you have a forced air furnace installed already and wish to change to a central heat and air system, it can be done. Because the forced air furnace uses ducting, very little will actually need to be changed.
Once you decide on the brand and model of air conditioner, installation can take less than three days. Well qualified technicians will install the system and may not even need to adjust the ducting. If ductwork is needed, it will be minimal for sizing and directional flow.
While this isn’t something you can do yourself, the cost is minimal compared to a fresh install without an existing system. Many standard-sized central air systems would cost between $3,000 and $5,000 to install. This is on top of the unit cost but is still less than a complete install for a new system.
People Also Ask (FAQ)
Can you put central air in a house with no ducting?
Any central air and forced air system will require ducting. If you are in a home without ducting, you can either install ducting with a new central air system, or opt for a ductless mini-split system that runs and cools without the need for ductwork.
Is a forced air furnace gas or electric?
Forced air furnace systems run on a lot of different fuel supplies. Electric units are possible, as are gas models. With gas, you have options for natural gas or propane fuel. You can even find furnaces that run on coal or wood. Natural gas and electric models are the most common, though, and both are completely viable solutions.
Can forced air heating be used for cooling?
Yes and no. Forced air systems refer to the use of ductwork and fans to force the air through the ducts to the individual rooms. However, a furnace is designed to produce and provide heat but cannot cool the air. You can, however, include an air conditioner system that uses the same ducting as the furnace to provide cool air to the home in addition to the heat from the furnace.
What is the cheapest heating system to install?
There are several options to consider when it comes to forced air heating systems. If the installation and setup of the system is the main concern, you will find the cheaper end options will be electric and gas boilers. Electric furnaces are also inexpensive to install, but running costs can get quite high. Heat pumps save the most money over time but have the highest installation costs by at least $1,000.
When it comes to controlling the temperature in your home, there are options for heating and cooling (or both at the same time). Forced air systems use ductwork in the ceiling or under the flooring to move air to the rooms of your home.
Forced air furnaces and central air conditioners are the most common solutions but have vastly different requirements. Even though they are both forced air systems, one heats while the other cools. It is also an option to combine the two for both heating and cooling.
Depending on your needs and expectations, we are sure that this forced air vs. central air has cleared up some confusion about the two systems. You should have a better idea about what you need and how best to approach your specific situation.