4 Reasons Your AC Is Blowing Warm Air

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4 Reasons Your AC Is Blowing Warm Air

10 February 2021
 Categories: , Blog


When the temperatures start to rise, your air conditioner may be pushed past its limit and break down. One of the most common air conditioning repair issues that homeowners face is an AC that blows warm air. Here are 3 common reasons why your AC is blowing warm air.

1. Frozen Evaporator Coils

The AC evaporator coils draw heat from your home's air to begin the cooling process. When the evaporator coils accumulate moisture, they start to freeze. The frozen coils prevent the transfer of heat. As a result, the AC will blow warm air.

One of the causes of frozen evaporator coils is system damage, refrigerant leaks, and poor airflow. You can try to thaw the frozen coils using a hairdryer or heat gun. Leave the AC off and turn it on when the coils have thawed. If this problem persists after following these steps, consult an air conditioning repair expert.

2. Incorrect Thermostat Settings

Another reason your AC may be blowing warm air is incorrect thermostat settings. Check your thermostat to ensure it's not set to heat. You should also confirm whether it's set to "on" or "auto." If it's on, the fan will blow even though the AC isn't cooling. 

Set the fan to auto, and make sure you select the cool setting. This will ensure that it runs during a cooling cycle. If these steps don't fix the problem, you may need an air conditioning repair expert to check your thermostat.

3. Low/Leaking Refrigerant

Your AC may blow warm air if it's low on refrigerant. One of the reasons is because there's a refrigerant leak. When the refrigerant leaves the system through a leak, it doesn't have enough charge to finish its cooling cycles. This is why the air indoors is warmer than usual.

Refrigerants are dangerous, and only an experienced technician can fix this problem. One of the ways of preventing refrigerant leaks is by scheduling air conditioning tune-ups. If you notice your AC blowing warm air, you should respond quickly to avoid complications.

4. Electrical Issue

Your AC has two main parts: the outdoor unit and the indoor unit. The AC's fan is in the indoor unit. This unit can only blow cool air if the outdoor unit is working. If the air blowing out of your vents is not cold, there is a possibility that there is a blown fuse or a circuit breaker has tripped.

Check the fuse panel or circuit breaker to ensure electricity is running to the outside unit. If there is no problem with the circuit breaker, there could be an electrical issue with the AC unit itself. In this case, you should call air conditioning services to troubleshoot the problem.