Perhaps you live in an area without central air. Maybe you are in a smaller apartment, and the management company won’t allow window units. Whatever the case, there is a need for windowless air conditioners.
We will cover the air conditioner options for rooms without windows, discuss how they work and what situations are best for them. We will also showcase the 5 best windowless air conditioners, review and compare them for your benefit.
Windowless ACs Compared
|Model||Venting Options||Cooling Area||EER||Noise Level||Price|
|Black & Decker|
|Window kit with hose||250 Sq. ft.||9.1||65 dBa||Check Price|
|hOmeLabs||Window or wall||600 Sq. ft.||10.1||58 dBa||Check Price|
|Pioneer WYS012-19||None||450 Sq. ft.||10.5||55 dBa||Check Price|
|Frigidaire||Window||550 Sq. ft.||12.5||58 dBa|
|Honeywell 525-729CFM||None||250 Sq. ft.||N/A||58 dBa|
How Do Windowless Air Conditioners Work
They design windowless air conditioners to cool the surrounding air without the need for a window to drain or exhaust out of. There are several types of windowless ACs, such as portable air conditioners and mini-split AC systems.
For the most part, the unit will sit in the room you wish to cool. There will be a suction fan that draws in ambient air, a method to cool that air and a fan to push the cooler air into the room. The cooling method can be an evaporator coil or a bucket of ice.
Mini split systems work much like a central AC, except there isn’t any ducting, and they can be installed in a single room instead of throughout the entire house.
Are Windowless ACs Any Good?
A windowless system isn’t designed to cool a whole house.
With some exceptions, they are only capable of cooling the air a few degrees in a smaller area.
Mini split systems are an exception as they can heat or cool a room of larger size.
Some portable units use internal evaporator coils and can run over 12,000 BTUs.
These systems can effectively cool up to 550 square feet.
All in all, a windowless system is a good investment if you need additional cooling or have a small room without windows that open (or windows at all).
Considerations When Buying Windowless AC
When you head out to buy your windowless air conditioner, be sure you have thought of everything. Below is a list of things to consider before making your final purchase.
Dehumidifier Feature Vs. Venting Options
One byproduct of cooling the air is condensation. There are two primary methods of dealing with this accumulation of water, evaporation or venting. Dehumidifier units have a collection tray that gathers the water, and what they cannot evaporate out will need to be emptied.
Venting units need a window or space to vent the exhaust air out to be effective. They, too, mostly require draining regularly. Vented units don’t add humidity to the air and don’t have a separate area dedicated to removing the added humidity, so they are easier to take care of.
Cooling Capacity (BTU)
For units that use evaporators, they rely on BTUs to power the cooling. Most portable ACs will range between 5,000 and 12,000 BTUs. Mini Split systems generally hover between 10,00 and 16,000 BTUs for single units and can be doubled or tripled depending on house size.
The higher the BTU, the more effective the unit is and will cool a more substantial space more efficiently. However, proper measurement of the space and power requirements are needed before you head out and buy the largest unit you can afford.
To accurately measure your space, you need to take the length of the room and multiply it by the width. This will give you the approximate square footage of the room. From there, you should also calculate the amount of furniture, windows or doors, and occupancy.
The more items you have in the room, the longer it will take to cool and requires a bigger BTU rating. If you are unsure how to account for furniture and the number of people, the square foot measurement will be enough.
Energy Efficiency Rating
The Energy Efficiency Ratio (EER) is a measurement of the ratio between BTUs and kilowatt-hours to determine how efficient the air conditioner is. The higher the EER value, the less it costs to operate, and the more efficient the machine is.
For windowless units, the average EER rating falls between 9.0 and 14.1 EER. If you do have a window opening then you can view our most energy efficient models here.
Noise Levels (dBA)
The decibel attenuation rating (dBA) is a measurement of the noise level after suppression. If a motor produces a high level of noise, the body of the unit should make it quieter. The dB rating for most windowless air conditioners should fall between 50 (real quiet) to 75 (noisy). Anything between these two values is acceptable for normal use. Read more on quiet portable AC units here.
Some units can use a thermostat to control them. These will mostly be the mini-split systems. Portable air conditioners will come with a built-in thermostat and control panel. Some mini-split units will have wireless controls allowing you to use mobile apps as your thermostat.
For the most part, you need to treat a windowless unit like it is a window or through the wall AC. The voltage requirements should be on a dedicated outlet, without the use of extension cords or power strips.
Mini split systems are generally hard-wired into the circuit breaker panel, so there isn’t a need for a specialized outlet or monitoring. HVAC technicians are mostly required for ductless and central AC systems.
Price & Warranty
The price and warranty will come into play as well. You don’t want to stray too far outside your budget for a new unit. Because these windowless air conditioners are designed for a specific job, you want to watch how much you spend on them.
Likewise, a warranty will cover you in the event something happens beyond your control. You need to ensure you read all the warranty details and follow all procedures for making a claim.
5 Best Windowless Air Conditioners Reviewed
1. BLACK+DECKER BPACT08WT
Best Small Windowless Portable AC
|Room Size (Cooling Area)||250 Sq. ft.|
|Venting Options||Window kit with hose|
|Noise Level||65 dBa|
|Warranty||1-year parts and labor, 5-years compressor|
The Black and Decker 5,000 BTU (8000 by the old standard) portable AC is the best small windowless AC on the market right now. This little guy can easily cool a room up to 250 square feet in a matter of minutes. You won’t need to wait long to feel the cooling effects of this machine.
The unit ships with a window kit for the exhaust fan and runs on 9 amps. While it can get noisy (65 dB), the benefits outweigh the issues. You may need to turn the TV up or have a harder time falling asleep because of the noise levels, but they aren’t so loud as to disrupt normal daily life.
The bucketless drain system is designed not to need emptying. It will dehumidify (certain regions) and still not overflow the drain pan. When being stored away, the reservoir will need to be emptied, though. If you live in a humid area, it will need to be emptied daily.
It is also not advised to run this unit constantly. A few hours at a time or when you are occupying the room. It isn’t made to turn on and leave for days or weeks on end.
- Easy 5-minute setup
- Cools up to 250 feet efficiently
- Bucketless drain system
- Can get noisy during standard operation
Best Large Windowless Portable AC
|Room Size (Cooling Area)||600 Sq. ft.|
|Venting Options||Window or wall|
|Noise Level||58 dBa|
The best large windowless portable AC is from hOmeLabs. This 14,000 BTU beast is still small enough to move around on its caster wheels. Don’t expect to lift and carry it around, though. The unit will effectively cool a room up to 600 square feet; however, it will drain your energy when used on high for long periods.
Even with an EER of 10.1, it isn’t the most energy-efficient machine out there. When it is running, you can switch to eco-mode, but the fan speeds may be too low. In this case, or if you need to get the room cool faster, turn off eco-mode and let it run for a while in standard operating modes.
Doing this will cause you to spend more on energy, but the cooling effects will be quickly noticed. Once the room is cool, you can save energy by turning on eco-mode, or leaving it in fan-mode operation to move the cooler air around until it begins to heat up again.
The good news is that you don’t need to get up every time. The hOmeLabs portable AC comes with a remote control that allows you to select mode, fan speed, and set the temperature. For larger spaces, this portable AC will keep you cold.
- Washable air filter
- Dehumidifies without draining
- Remote control operation
- Fan speeds may be too low
3. Pioneer WYS012-19
Best Ductless Mini Split AC For Windowless Rooms
|Room Size (Cooling Area)||450 Sq. ft.|
|Noise Level||55 dBa|
The Pioneer WYS012-19 mini split AC is the best ductless AC for windowless rooms. It requires professional installation to maintain the warranty. That warranty, 5-years, covers everything in the system. Once installed, you won’t have to worry about a thing.
The small mini-split system uses 12,000 BTUs to cool 450 square feet effectively. For most installations, a single room will be sufficient. You won’t need to worry about condensation, draining, or exhaust, either.
The heat pump unit outside will handle everything for you while you sit back, relax, and enjoy the fresh, cool air. The one downside is that it isn’t the most efficient mini-split system on the market. However, it isn’t the worst, either. With an EER rating of 10.5, you shouldn’t notice any major spikes in your electric bill.
Some mini-split systems require you to adjust the vent louvers to specific angles to prevent condensation build-up. This Pioneer system has automatic louvers, so you don’t have to worry about your floor or furniture under the unit getting dripped on.
- Heating and cooling in one unit
- Remote operation
- Permanent filters (washable)
- Requires professional installation
- Not the most economical mini-split system
Best Smart Portable AC For Windowless Rooms
|Room Size (Cooling Area)||550 Sq. ft.|
|Noise Level||58 dBa|
|Warranty||1-year parts and labor, 5-year compressor|
When you want the best smart windowless portable air conditioner, look no further than the Frigidaire Cool Connect. This 12,000 BTU portable AC has everything you need and nothing you don’t. It even comes with a 1-year warranty on parts and labor and a 5-year warranty on the compressor.
It doesn’t dehumidify as well as some other models, but the drain system is easy and doesn’t overflow as long as you pay attention to the warnings. The wireless connectivity is novel and works well. The mobile app is intuitive and will allow you full control, even going so far as to set schedules for use.
You can effectively cool up to 550 square feet with this portable unit, which also looks sleek and stylish (except for the bulky exhaust hose). When in use, the machine is whisper-quiet, ranging in noise levels between 54 and 58 dB. In most operation modes, you won’t even notice it is on, except for the cold air moving around your room.
With an EER of 12.5, it is one of the most economical portable ACs on the market. While all electronic devices will raise your electric bill, this unit will operate in standard mode for a full year costing an average of $120 to do so.
- Highly efficient AC
- 12,000 BTU for cooling up to 550 sq. ft.
- Wireless connectivity for use with mobile app
- Can be difficult to move on carpet
- Window kit is challenging to adjust and install
5. Honeywell 525-729CFM
Best Evaporative Cooler For Windowless Rooms
|Room Size (Cooling Area)||250 Sq. ft.|
|Noise Level||58 dBa|
Swamp coolers are an integral part of hot weather life. The Honeywell 525-729CFM evaporative cooler is the best swamp cooler for windowless rooms. It can throw cold air up to 32 feet, and with the addition of the ice bucket, that air can be frigid.
It is ideal for smaller rooms or targeted cooling in larger rooms. You won’t be able to cool an ample space that effectively, but the small area it does cover is highly noticeable. This cooler is a high-powered fan blowing air over ice to keep things cool. When the ice melts, the cold water will continue to cool the air for a few more hours.
There isn’t any draining since the fan doesn’t produce condensate. You will need to refill the ice bucket often on hot days, though. For the most part, an ice tray will last for 4 hours, but in temperatures over 95 degrees (F), this can be as low as 1 hour.
It won’t replace your air conditioner, and it isn’t as effective in large spaces as a portable AC, but if you want cold air on you, or need additional cool air while you sleep, the Honeywell system is your answer.
- Easy to use
- Ice tray can cool air for several hours
- Ideal for targeted cooling
- Not effective in high humidity areas
- Water can slosh out if moved while full.
Installing Windowless Air Conditioning Units
Windowless air conditioners, depending on type and size, aren’t too difficult to get up and running. You will need a way to vent the exhaust, and most portable units will ship with a window hose that fits in a window opening to vent the hot air outside.
If you don’t have a window, you can put the vent in an unused room to help keep your occupied space cooler. For mini-split systems, you will need an HVAC technician for installation. These require special installation requirements, permits and must meet code. The professional installer will ensure you meet all the needed requirements.
You can find detailed owner’s manuals online through a simple Google search for your brand or model number. Also, most manufacturers will post how-to videos on YouTube for you. Check out this installation video from Honeywell.
Care, Safety & Maintenance
When using a windowless air conditioner, you will need to perform routine maintenance. This will include cleaning or replacing the filters, emptying the drain pan, and keeping the unit clean. The intake vents will need to be vacuumed out, and on certain models, you should clean out the exhaust hose as well.
Draining the water pan will vary from model to model. Some will not need to be emptied as they will evaporate themselves. Others require you to remove the pan and empty it yourself or to connect a garden hose and drain it that way. Your model will have draining instructions in the owner’s manual.
Frequently Asked Questions
What are some common problems that may arise with ACs in windowless rooms?
The most common issue is overuse. If the units are not properly vented, they will end up recycling the same hot air they attempt to exhaust. This will make the units work harder to cool the room, in turn, raising your electric bill or causing the machine to burn out.
What can be done to extend the life of an AC Unit?
Regular maintenance, cleaning, and care will be the best method of prolonging the life of your AC unit. Replacing or cleaning the filters is the most significant maintenance procedure to follow. It also helps not to run the unit for prolonged periods. Unplug and store in a cool, dry place when not in use and make sure that any issues presented are fixed immediately.
Which models on our list offer heating as well as cooling?
From our list, the Pioneer Air Conditioner WYS012A-19 is the only model to offer heat as well as air conditioning.
Where is the best place to buy this type of air conditioner?
You can buy a windowless AC at any brick and mortar home improvement store such as Home Depot or Lowes. Most local hardware stores, like Ace Hardware, will carry them also but these places will usually only stock a couple of options.
The best online places to buy AC units are through Amazon or Sylvane. When purchasing online, you can get faster shipping, find the right replacement parts (filters, etc.), and get deals on models the brick and mortar shops no longer carry.
As you can see, when it comes to keeping a single room in your house or apartment cool, you have options. Depending on your specific needs or restrictions, it can be challenging to figure out which model is best for you.
If you are in doubt, we recommend you go with our top pick, the BLACK+DECKER BPACT08WT. This portable AC is lightweight, has enough features to make it viable and cools a small room efficiently.
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