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Why is My Air Conditioner Blowing Warm Air?

AC Blowing Warm Air

During the hot summer months, it is critical that your air conditioner is working properly. There are times, however, that certain problems cause the AC unit to blow warm air instead of providing your home with cool air. At Cates Heating and Cooling, we want our customers to know what the problem could be and whether they can fix it themselves before giving us a call. Here are a few reasons that could cause your air conditioner to blow warm air.

Thermostat is Set Improperly

The first thing you should check any time you notice that your home feels uncomfortable is the thermostat. You may think that the thermostat is set to a certain temperature, but someone else could’ve changed the setting or the switch that designates heat vs. cool could’ve been bumped and switched. The same could be true for the “on” switch. Additionally, if the thermostat is set to “on,” the fan will blow even when cool air isn’t being produced, which can make your home feel much warmer. It is best to leave the setting on “auto.”

Before giving up on the thermostat, try changing the batteries as well. Weak or dead batteries could also lead to your air conditioner not cooling to the temperature that you desire.

Unit is Leaking Refrigerant

A refrigerant leak is a big problem, and it is one of the most likely causes for your AC blowing warm air. Since refrigerant is what allows your air conditioner to produce cool air, a leak will quickly end cool air flow in your home. Since your air conditioner’s refrigerant is part of a closed loop, you shouldn’t need to add refrigerant unless there is a leak, and when you have a leak, you need to fix the leak before adding refrigerant back into the unit.

If your AC unit is leaking refrigerant, call a professional HVAC repair company to survey the damage for you, and make any necessary repairs.

Unit is Frozen

Did you know that your air conditioner can freeze? When your air conditioner forms a block of ice inside the unit, and typically no air will move through the unit. If you determine that your air conditioner is frozen, you need to let it thaw. To do this, turn the unit off for a couple of hours. However, the unit may freeze up again. If it does, then you should contact an HVAC repair company to look over the unit.

You can prevent your unit from freezing by keeping the thermostat set between 70°F and 72°F on the “auto” setting. When you set your AC temperature too low, you run the risk of freezing the unit.

Air Filter is Dirty

A dirty air filter can cause numerous problems for your HVAC unit. If you notice the air in your home is starting to feel warmer than expected, you might need to switch out your air filter. If your air filter is too clogged to properly allow air to blow through it, you will notice that the air coming out of your air conditioner is warm.

Condenser Unit is Dirty

Since the outdoor component of your air conditioner is constantly exposed to the elements, it is likely to get dirty over time. Unfortunately, when the outdoor unit is dirty, debris can cause a blockage and interfere with the air conditioner’s ability to cool your home. You need to clean the condenser unit and remove any debris that could be causing problems.

Circuit Breaker Has Been Tripped

If the power has been cut to the HVAC unit, you aren’t going to feel any air coming out of your vents. Occasionally, circuit breakers trip and need to be turned back on. The trip is caused by an overload of power, which triggers the circuit breaker to shut off to prevent any problems. You can fix this by flipping the tripped breaker back to the “on” position. If the breaker trips again, you should call a professional HVAC technician or electrician to determine the cause of the trips.

There are other reasons that your AC unit could start blowing out warm air, so if your problem doesn’t appear to be one of the few listed above, contact a professional HVAC repair company to check out your unit. In the Kansas City Metro Area, Cates Heating and Cooling can help get your air conditioner back in working order as soon as possible. Just give us a call at 913-888-4470.

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