Why Is My Air Conditioner Blowing Warm Air?


In the heat of the summer, the last thing you need is to have your air conditioner blowing warm air. Having your air conditioner blow warm or hot air when you need to escape the simmering heat can be an absolute nightmare. While there are many different reasons why your air conditioner is blowing warm air, here are some of the most common causes you may find:

Thermostat Issues

While it may seem obvious, one of the most common causes of air conditioning temperature issues has to do with the thermostat. Whether it is tampered with by kids, accidentally changed, or intentionally turned off and then forgotten, there are many different reasons the thermostat may have incorrect settings. If you experience issues with your air conditioner blowing warm air, check the thermostat first!

Dirty Filter

If left unchecked, dirty air filters can wreak havoc on the inside of your air conditioning unit. Most people don’t change the air filter in their AC until it is too late and something goes wrong. While a dirty air filter alone won’t cause your air conditioning system to blow warm air, it can contribute to the problem and reduce cooling effectiveness significantly. An air filter clogged with dust and debris can completely block air from entering the system, which makes the coils unable to remove heat, so the system’s fan just blows heat back into your space.

Problems with the Outdoor Unit

Air conditioning systems are made up of an indoor evaporator/air handler unit and an outdoor condenser unit. They work together to consistently blow cold air into your home. If your indoor system is working fine, air will still blow. However, if your outdoor condenser unit is not working properly, there will be no cooling and your AC will blow warm. A blown fuse or tripped circuit breaker may cause your condenser unit to lose power. You may also notice issues if your condenser unit becomes blocked by debris and dirt.

Refrigerant Leak

One of the most common reasons for your AC blowing warm air, a refrigerant leak will make it impossible for your AC to produce cool air. Refrigerant is the substance that flows through your air conditioning system that makes cooling happen. You should never have to add refrigerant unless you have a leak. Depending on the size of the leak, cooling loss can happen slowly or all at once. With one of the most popular older refrigerants being phased out by January 2020, it will soon become increasingly expensive to replace your refrigerant.


Home Comfort Experts are here to help you get your AC back to blowing out cool air. We will take into account your budget, heating and cooling needs, and energy saved. Contact the heating and cooling professionals at Home Comfort Experts today to learn about the ways we can help you. We serve Northern Indiana and Southwestern Michigan from our 12 locations. Give us a call at (574) 255-4600 to learn about our full complement of heating, cooling and plumbing services.

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