How to troubleshoot most window air conditioners problems

Sep 12, 2022   |   10 min read


How to troubleshoot most window air conditioners problems


In the beginning, we believe it's important to point out that if you follow regular window AC maintenance, you'll pay less power and keep your space cool and comfortable without any issues. Getting your window AC serviced during and after the close of the summer is essential. Let's look at the most frequent problems related to window ACs.

Window air conditioners can be lifesavers during hot summer months, offering a continuous flow of cool air, but they can cause a lot of damage when they cease to function. They usually stop working on the hottest day of the year.

Let's look at the way window air conditioner’s function and a list of the most common problems, including troubleshooting suggestions and ways to resolve them, if possible, before calling an HVAC expert to help you save. This is also true for window-type heat pumps.

What is a window air conditioner?

  • Window air conditioning is the same as a bigger AC unit. However, it is compactly packed in a box that fits inside windows with half inside and the other half outside. Because of its compact dimensions, it is mainly used to cool rooms.

  • The grill cover is another side of the room to allow cool air to enter your home. Between the grill and behind it is a filter that can be removed to collect dust in the airflow, making the air clean. Filters must be regularly cleaned to ensure maximum performance and the most extended life. It is easy to accomplish this; You need to unplug the appliance from the power source and remove the front cover and a filter.
  • Specific AC units could include replaceable filters. Others utilize a fine mesh that can be cleaned by washing it in soapy water and dried and rinsed before replacing the filter.
  • Clean the internal filter every 2 or 3 months unless you are in a dusty area or have pets. In that case, it's best to do it once per month. Recommended. It's easy and quick to ensure that your system operates correctly and keeps your air fresh.

How do you get rid of the dirt inside your Window AC

  • If you take the cover of the window AC off, you can view the evaporator coil. It has fins made of delicate material to direct the flow of air throughout the unit. The fins get blocked in time and require to be cleaned. The coil has a fan that can blow air across and out into the room.
  • To look at the back of the window of the AC system, it is required to be removed and moved outside to be cleaned if you live on the surface and have access to it. After dismantling and opening, you'll see the compressor unit located between the evaporator and the condenser coil. It comes with a fan that helps force hot air back into the air.
  • If the unit is opened, it is easy to maintain with an affordable cleaner purchased from your local HVAC store. Just spray the coils thoroughly and allow them to soak for a few hours, then clean the dirt with fresh water.

Verify the coil fins

  • Since the fins of coils can be damaged, it's not recommended to clean them using anything hard or rough. Make sure to use a gentle spray of water to get rid of the dust. If any fins are bent or broken, you may straighten them with fin combs. This can improve the flow of air through the unit.
  • Dry the unit well before installing it again. An additional pair of hands can be helpful during this procedure in the event of an accident.
  • If you maintain your air conditioning unit in the windows every time, you will give impressive results. However, it will eventually be a problem and fail you at the most appropriate time.

Summer awakes

  • If the window's air conditioning has not been running throughout winter, it is essential to test it thoroughly before running it in the spring and summer.
  • Take it out of the window or when it's in storage, unzip it and look for any nests, bugs, or other small mammals that might have occupied the space in the winter months. Please clean it up carefully using the vacuum, and then gently clean the coils to remove any dirt. If any fins have been broken, it is possible to replace them using a fin-comb by setting it according to the exact layout of the fins for every inch in the coil.
  • Clean the filter and inspect the blades of the fan for damages. Straighten them gently to ensure smooth running.
  • After the unit has been cleaned and dry, you can re-install it and ensure it's in a great state. Examine for leaks of every sort. They could be a sign of something more serious and, when caught early, could be easily repaired. If you allow it to go, it could cost you a lot of money and could not be fixed for a long time.

Freezing up is the cause

  • Another problem that can be found in window AC is that it freezes, and this could be due to dirty or blocked coils. Overheating can result from freezing and can reduce the effectiveness of the unit. There is a possibility that the unit is experiencing an issue that requires repair or the refrigerant is not has been topped up.
  • If you select the low fan setting with a lower temperature setting on the AC in your windows, it'll most likely freeze. The AC requires adequate airflow to function efficiently, so operating it at a higher setting is recommended. The only reason to reduce the speed of your fan is to reduce the humidity in your room when it's too high.
  • The ideal temperature should be around 68 F A temperature lower than that could cause the unit to get frozen.
  • To prevent problems with the compressor, such as overheating, you can use the garden hose to clean it.

Windows AC Checklist

  1.  Are you experiencing too much sun? If your AC is situated in an area exposed to direct sunlight during the summer heat, it'll have to be more efficient in cooling the space. If you're faced with a decision, make it move to a more shaded area. If you don't, you can keep your shades or curtains pulled up during the day to block the sun's rays and keep them from warming your home.
  2. Are warm air leaks into your home? Examine the seals on windows to ensure that the hot air doesn't get into the unit, and cold air isn't leaking out. Re-seal your unit using weather stripping, if needed.
  3. "Most windows that are new are equipped with insulation panels that can be placed over the plastic, adjustable panel on the sides," claims Chris Regan, who is CR's senior air conditioner tester. "But to get the most efficiency from your unit, it is still necessary to apply strips of weather-proofing around the outside of the unit. Always follow the manufacturer's instructions for installation instructions and safety equipment."
  4. Does your window AC sound like it is being agitated? Air conditioners can make a lot of noises, including the sound of the fan and the sounds of the compressor cycling between on and off. However, if you hear the sound of vibration, this could mean that your unit was put in place improperly. Check that it's positioned correctly in the window. Then go through the installation guidelines in the owner's manual to ensure no mistakes.

Troubleshooting Guide -12 most common problems

This guide to troubleshooting covers 12 of the most frequent problems with windows air conditioners. Most of the time that the absence of simple maintenance causes the most common problems. A little care and attention can prevent most of these issues, and your system will perform hard for you daily. Do not ignore it, and it'll bring you back.


The AC does not work.

Possible causes: no electricity or the unit was switched off or disconnected.


  1. Turn off the power.
  2. Check the plug, cable, or breaker.
  3. Don't make use of extension cords.


Broken breaker tripped or reset button.

Possible reasons Potential causes include: Power surge, overloading supply, or faults within the device.


  1. Reset the breaker (or alter the fuse with the appropriate rating) and reset the button on the device.
  2. Ensure the power supply is sufficient to support the load.
  3. If you are unsure, contact an electrician.


Breaker tripping frequently.

Possible causes include an overloaded supply or a fault with or in the AC unit.


Contact an electrician or HVAC technician.


The fan creates an insignificant amount of warm air.

Possible causes: Check your thermostat setting.


Lower the thermostat to check if the unit is cooling.

Problem # 5: 

Fan is working, but it doesn't cool.

Possible reasons: 

Dirty filters or coils that are causing insufficient airflow.

Solution Cleaning coils and filters frequently to get rid of dirt.


The unit is turned on and off frequently.

Possible causes: 

Dirty filters and coils that cause insufficient airflow.


Cleaning coils and filters frequently to get rid of dirt.

Problem # 7: 

Fan is vibrating.

Possible causes: 

A fan is clogged or blocked by debris or a malfunctioning motor.


Clean and check the fan and replace the damaged blades. If it is defective, call an HVAC technician.

Problem # 8: 

Fan is not working.

Possible causes: 

Check the switch settings.

Solution If the settings are proper, the switch might be defective.

Problem # 9: 

Fins damaged on coils.

Possible causes: 

Fins can be susceptible to damage and may hinder airflow when bent.


Avoid excessive handling while cleaning and gently straighten fins using the fin comb.

Problem # 10: 

Leaks of coolant.

Possible Causes: 

The coils may be damaged.


Contact to speak with an HVAC technician.

Problem # 11: 

The compressor isn't running.

Possible causes: 

Examine the connections for any looseness.


Contact the HVAC technician.

Problem # 12: 

Condensate leaks into the home.

Possible causes: 

The unit could be situated at an inwards angle, and condensate may not be draining into the tray.


Alter your unit's angle to ensure that condensation drips into the tray properly.


Always unplug the appliance from power sources before taking off the covers to perform maintenance or troubleshooting.

It's the simplest of things

It's a good idea to clean your coils and filters at least once a year to ensure that you have good air circulation through your unit, as air conditioning requires continuous free air circulation to operate effectively. Cleaning your filters can be done fast, and removing dirt and debris from the coils can bring your unit back to a new state.

It's only a short time and will ensure that your system runs smoothly and efficiently throughout the year. Consider how often you wash your vehicle. It doesn't have to be well-maintained to function. However, you still take care of it. So why shouldn't your air-cooling system?

Be alert to leaks of any type; they might indicate something more serious, and if discovered quickly, they can be fixed easily. If you allow it to go, the problem will get expensive and might not be repaired for a long time.


As always, it's up to you to make the option, and if you invest a bit of time maintaining the condition of your window AC it will reap dividends with a guarantee. It's not that difficult to perform and is extremely worthwhile, not to mention it can save you money for a long time.

Window Air conditioners have been constructed and designed in the same manner as the top-quality specifications of full-sized units and can last for a long time If you can maintain the.

And then you can relax in a tremendous flow of cold air on one of the hottest days, knowing that you did the right thing. Plus, you didn't have to pay for an expert This time.


Frequently Asked Questions