If your house isn't cooling down like it should when you turn the air conditioner on, you may want to feel the air coming out of the register vents. If the air isn't chilly like it should be, there is probably something wrong with your air conditioner. Here are three possible causes of an AC that blows warm air and what an air conditioner repair technician can do to help.

1. The Thermostat Is Faulty

Check the thermostat first. If your AC blows warm air the first time you turn it on in the summer, you may still have it set to operate the furnace. If you double-check the settings, test the thermostat by adjusting the temperature to get the AC to kick on.

A thermostat can go bad, or the wiring can get loose and keep the thermostat from controlling your AC. An air conditioning repair technician might take the thermostat apart to see if it is dirty or has loose wiring. If the thermostat can't be repaired, the technician can replace it with a new model.

2. The Refrigerant Coils Are Dirty

When your AC blows warm air, a refrigerant problem is a possible cause. Even if your AC has the proper amount of refrigerant, the refrigerant may not be able to do its job if the coils are dirty. There are two coils in a central air conditioning system. One is inside and the other is outside. The coils are connected by copper tubing, and refrigerant circulates through this system.

The coils outside might get coated with dust, dirt, leaves, or other debris. Dust and grime can also coat the indoor coils, especially if you don't keep up with replacing the filter. If you're running your AC for the first time, it could have a buildup of grime from a long winter and spring.

Since several things can cause the refrigerant system to have problems, the repair technician may check all the parts in addition to cleaning the coils to ensure the problem is found and corrected.

3. The Refrigerant Is Leaking Out

Hopefully, the air conditioner repair technician will find a simple cause for your AC problem, but a refrigerant leak is always a possibility. If one of the coils or copper lines developed a pinhole leak over the winter, the refrigerant may be leaking and too low to chill your house properly.

Repairing a refrigerant leak can be a complex and costly type of air conditioning repair since the refrigerant also has to be filled. First, the leak has to be found and repaired, which is sometimes tricky if there are multiple leaks. In an extreme case, the technician might need to replace the coils, but repairs are often possible as long as the leak can be found.

Your AC won't work without refrigerant, so fixing the problem by repairing the leak or getting new coils is necessary so you don't spend the summer in a hot and stuffy house.

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