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Common Air Conditioner Problems & Solutions

Air conditioner in window A window air conditioner can provide the much-needed relief you need when the temperature rises, especially in homes without central air. To ensure you stay cool all summer long, it’s important to know how to troubleshoot some common problems with the unit. You may not be able to fix every problem, but this will give you an idea if you should repair the unit or purchase a new one.


My air conditioner won’t turn on.


The first thing to do if your A/C unit won’t turn on is to check for power. Is the air conditioner plugged in? If so, test the outlet by plugging something else into it. If the outlet is receiving no power, check your circuit breaker.


If the A/C is receiving power but still doesn’t turn on, there are a number of issues that could be wrong and would require repair, including the wiring, thermostat, compressor, selector switch, or control board.


Checking a dirty air conditioner filterMy air conditioner isn’t cold enough.


This is a common complaint and the reason it’s important to purchase the right BTU size air conditioner for the space you are trying to cool. Check your BTU size to see if you purchased the right size for your space. You may need a new air conditioner with more BTUs to get the job done.


If you have the right size air conditioner, use a thermometer to get the temperature of the room and compare that to the temperature you want it to be.  If there is a 15 degree difference you may be asking the unit to do more than it's capable of. Try resetting the temperature to 10 degrees lower than the room temperature.


If the difference with the thermometer is less than 15 degrees, check the air damper. If it's open, it will bring in outside air, which is bad for the unit’s efficiency. Be sure to also check your back cover; many people forget to remove this cover after the winter season.


Lastly, check the condensing coils, which are located on the warm end of the A/C unit. Remove the air conditioner cover to access the coils and clean them with a soft brush.


My air conditioner isn’t blowing out any cold air.


If you’re not feeling any cold air coming from the unit but the fan is blowing, make sure the thermostat is set appropriately. Next, check the compressor motor, which is a small case inside the air conditioner. If it is humming continuously, it could be the condenser, evaporator or compressor, all of which would need service from a professional.


My air conditioner is leaking water.


If you find your A/C unit is leaking water, this could be a sign that it wasn’t installed properly. Re-check the manual’s installation instructions to be sure the installation was done correctly. Most likely you may just need to tilt the unit back slightly to allow water to run off.


 If you have consistent problems with your A/C unit and you have gone through all the troubleshooting steps, the unit may need service from a professional or it may just be time for an upgrade. An average window air conditioner has a life span of 8 years, and this varies depending on how often it is used and how well you maintain the unit.


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