How Much does It Cost To Run A Window Air Conditioner Per Month? HVAC Expert Explains

Air conditioners (AC) are one great invention that helps us cool off, especially when it is hot. However, any appliances that alter temperature tend to consume more electricity. The same could be said about AC. 

How much does it cost to operate a window air conditioner per month? It depends on the British Thermal Unit (BTU) rating for an AC regarding the cost to operate a window air conditioner per month. You may assume a 5,000 BTU window AC costs around $0.065 to $0.195 per hour. Energy prices and your usage may also influence the final figure.

According to HVAC experts, the best way to ensure efficient energy use for your window AC is to clean it. Cleaning avoids having the AC work too hard to cool the room since the systems are not blocked by dust and debris. 

Consider using the Nu-Calgon Evap Foam AC Coil and Evaporator cleaner to clean your window AC’s evaporator and coil. It comes as a foam spray and does not require you to rinse after application. Get yours delivered to you by clicking here.

How Different are Window and Split AC?

In general, window and split AC differ in form, price, maintenance, and performance. Window and split AC may also give us a different user experience. Split AC may be useful to cool a larger space while keeping the noise low, while window AC may be suitable to cool a small room.

AspectsWindow ACSplit AC
Form FactorAll-in-one, box formSplit into outdoor and indoor units
PriceCheaperMore expensive
InstallationEasierMore Complicated
MaintenanceEasierMore Elaborate
Power ConsumptionHigherLower

Window and split AC perform a similar job to cool down space, making you feel more comfortable. They, however, differ in form and performance.

Form Factor: Window AC has a box-like shape and contains all the parts inside it. The front face is where the control, cool air blower, and evaporator are. The back face contains the condenser, and the motors and compressor. 

Split AC instead splits the parts. The front face is gathered together and is named the indoor unit. This is the part you normally see indoors. The condenser, motor, and compressor are placed with the outdoor unit. These two units are connected by pipes. 

Price: Pricing can be subjective, as the form factor is not the only reason influencing price. However, when both run at the same BTU, window AC tends to be cheaper than split AC. This is because it may be easier to make a window AC than a split AC.

Installation: Window AC is easier to install as they come as a single unit. Most people simply place it by the window, lay out the piping, plug in the switch, and power up the AC. Split AC requires more elaborate installation work, and professionals are often required to do the work well.

Noise: Window AC tends to be noisier compared to split AC. This is because the motor unit is not separated from the AC, meaning it is closer to you. The noisy outdoor unit can be placed further away for a split AC, removing the noise. 

Maintenance: Window ACs are easier to maintain compared to split AC. This is because the unit is standalone, and there are no major piping and connection issues to work with. Split AC may require professional maintenance and troubleshooting as they are more complex.

Power Consumption: Window AC tends to consume more energy than split AC by a larger margin. This could be explained by the distance between the heating and the cooling element, resulting in inefficiency. 

How Much Does It Cost To Run A Window Air Conditioner Per Month?

Generally, running a window AC per hour may cost you around $0.065 to $0.195. However, the price may change based on many factors. These factors include energy prices, the output of the AC, and the hours you run the AC. The AC’s operation location and condition may also be considered.

There are many ways to calculate the cost of running a window AC, and many factors must be considered. As such, the calculations and numbers shown here may be best seen as guidance, not a definite answer. 

Assuming that your window AC has the EER (Energy Efficiency Rating) of 10 and that your energy bill is at the US average of $0.12 per KWh (Kilowatt hours). In that case, your hourly costs should be as follows:

Window AC Unit (BTU)Estimated Cost Per Hour
5,000 BTU Window AC$0.065 per hour
8,000 BTU Window AC$0.085 per hour
10,000 BTU Window AC$0.117 per hour
12,000 BTU Window AC$0.143 per hour
15,000 BTU Window AC$0.195 per hour

You may now use this as a calculation basis to determine your energy cost. Simply look at the BTU rating of your AC and the cost per hour. 

Then, roughly estimate the average daily hours you run your AC and times 30 days. This will give you a monthly hourly use of your window AC.

Take the hours and times it against the energy cost per hour, and you should arrive at the estimated monthly cost to run your window AC.

For example, you run a 5,000 BTU window AC for around 5 hours daily. That translates into around 150 hours a month. Take 150 and times that against the estimated hourly cost of $0.065 per hour. That calculates up to $9.75 per month. 

Again, do understand that many other factors may influence your final energy bill. Things such as your AC’s condition, operation temperature, and how cold you are running your AC may also influence your energy consumption. 

Why Are Window AC Less Popular Now?

Window ACs are generally less popular now for many reasons, such as being noisy and having an outdated design. Window ACs also consume more energy and may damage your window if not well supported. Window AC exposes your house to break-ins since it leaves a gaping hole exploitable by criminals. 

Noisy: Window ACs are, in general, noisier than split AC. The reason is simple. Window AC has all the parts enclosed in a single box. This means that the noisiest part of the AC, such as the motor, is also in the box.

As a result, the motor is much closer to your ears, meaning you can hear it humming every time you run your AC. This makes window AC not a good option if you want to cool your bedroom since many people like to sleep quietly.

Outdated Design: Window AC has been around for a long time, since 1929. The design might have changed, but the overall concept remains. Many old, dilapidated buildings are also equipped with window ACs. 

As a result, people tend to associate window ACs with old, outdated designs that do not fit modern buildings and houses. Plus, a split AC just looks much more elegant, anyway.

May damage your window: Window ACs are commonly mounted on your window. The most straightforward way to mount your window AC is to raise your window sill, place the AC, and bolt it down. Then you close off the window sill and then seal any gaping hole. 

However, window ACs are heavy and may need you to mount good support to keep them sturdy. If not, it may fall and break your window. 

High energy consumption: Window ACs are generally less energy-saving than split ACs. The difference can be rather drastic. Most window ACs have an Energy Efficiency Rating (EEC) of around 8-12, while basic regular split ACs may have an EEC of around 15-20. Some really energy-efficient split AC can even reach EEC as high as 42.

Safety Concerns: Another major issue with window AC is that it leaves a gaping hole in your window or house. This can easily be a good entry point for thieves or criminals to break into your house. 

Once the AC is removed from the window, the housebreaker can easily climb in. This does not happen with split ACs, as the holes must be made only several inches long.

How To Save Energy When Using Your Window AC? 

You may run it at a higher temperature to save energy when using window AC. You should also turn off the power completely and set a timer to avoid overusing it. You should also enclose the space you intend to cool and regularly clean your AC.

Run At A Higher Temperature: Many AC users have weird habits. They like to power the AC at the maximum, cooling the room or space to such low temperature they instead have to wear something to keep them warm. 

This is unnecessary, as running the AC temperature too low may not just use more energy but force the compressor to work hard. 

Turn Off The Power Completely: Many AC users also have a habit of switching the AC power off only through their remote control. To ensure savings, turn off the power switch that supplies power to the AC. 

This is because if only switched off via remote, the compressor may continue to run, or in electricians term, to idle load. This consumes electricity, which may result in higher energy bills.

Set Timer To Avoid Overusing: At times, we run out of AC to the point that we actually feel too cold. Setting timers may help prevent this from happening. Once the AC runs for some time, it automatically stops. This prevents the AC from being overrun, which will help you reduce your energy bill.

Close The Space: If you intend to cool down your room, ensure to close the doors and windows. This helps the cool air to remain inside your room. The cool air is then sucked into the AC, which means the compressor does not need to work overly hard to cool the air. This, over time, saves you energy bills.

Clean Regularly: One way your window AC may use a lot of energy is when it is not well-cleaned. Dust, dirt, mold, and grime can easily cause the AC to work inefficiently, resulting in higher energy consumption. 

How To Clean Your Window AC?

To clean your window AC, start by gathering the cleaning materials and tools. Remove the front face cover, and protect the control board by wrapping it in a plastic bag. Clean the cover, and filter with soap. Then clean the evaporator, and the condenser with a vacuum, brush, and cleaning spray.

Window AC PartsHow To Clean
Front PanelClean with dishwashing liquid, and agitate with a painter’s brush.Rinse and air dry.
FilterSuck out thick dust with a vacuum cleaner.Clean with dishwashing liquid, and agitate with a painter’s brush.Rinse and air dry.
EvaporatorSuck out thick dust with a vacuum cleaner.Spray 3% Hydrogen Peroxide solution into the fins, and brush the dirt with a painter’s brush. Apply a thick layer of Nu-Calgon evaporator cleaning foamAllow foam to dissipate and dry off.
CondenserSuck out thick dust with a vacuum cleaner.Spray 3% Hydrogen Peroxide solution into the fins, and brush the dirt with a painter’s brush. Apply a thick layer of Nu-Calgon evaporator cleaning foamAllow foam to dissipate and dry off.

To clean your wIndow AC is a rather simple affair. It can be done without requiring special tools or equipment. This also means you can easily clean it yourself. 

To start, prepare the following materials:

  • Vacuum cleaner
  • Screwdriver
  • A small plastic bag
  • Paper towels
  • Spray bottle
  • Painting brush
  • Dishwashing liquid
  • 3% Hydrogen Peroxide solution
  • Evaporator and Coil cleaner, we recommend Nu-Calgon
  1. Unplug the window AC from the power source. 
  2. Take off the front panel. You may need to use a screwdriver. Check with your user manual for proper instructions for your AC model. 
  3. Once you remove your front panel, your front panel controls may be hanging and exposed. Cover it by wrapping it inside a plastic bag. This protects it from moisture when you clean your AC.
  4. Remove the air filter. 
  5. Suck away the major dust dirt from the filter using a vacuum cleaner. Then perform further cleaning using the painting brush and dishwashing liquid. Rinse and air dry. 
  6. You may also clean the front panel if you see the need to. 
  7. Next, power up your vacuum cleaner, and suck away the dust and dirt from the evaporator and condenser. 
  8. The evaporator is the fins on the front side of your AC. The condenser is the fins on the back side of your AC.
  9. Fill the 3% Hydrogen Peroxide solution into a spray bottle, and start spraying into the evaporator and condenser fins. Use the brush and run it through the fins to remove dirt inside. 
  10. As you do so, lay paper towels at the base of the evaporator to catch any dirt falling off. 
  11. You may repeat the same on the condenser fins. 
  12. Thoroughly clean and protect your condenser and evaporator with Nu-Calgon Evap Foam AC Coil and Evaporator cleaner. Shake well, and spray in a generously thick layer of foam. Allow up to 15-20 minutes for the foam to dissipate and dry. 
  13. Once the other parts are dry, reinstall all the parts back. Power up the window AC and feel the difference!

Aron Blake

I am the lead copywriter on Homezesty and the Webmaster. I have a lot of experience in home renovations and the creation of style. I enjoy writing and sharing my tips on how to create the best living environment. My Linkedin Profile, My Twitter Account

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