If your home feels warm no matter how long your air conditioner runs, there’s a chance your AC is just blowing hot air. You can test for this issue by placing a hand near an AC vent and seeing whether the air feels room temperature or warmer. There are a lot of reasons that your AC might be blowing hot air. Some are just harmless, easily fixable mistakes, while others indicate a serious problem with your system. Being able to figure out the cause of the issue will help you figure out how to get cold air again.

Your Thermostat Settings Are Incorrect

If you notice hot air, the first thing you should do is check your thermostat. It can be surprisingly easy to bump into a thermostat and accidentally change its settings. Of course, if your thermostat is on “HEAT,” hot air will be coming from your vents. Another potential reason for hot air can be your fan settings. If your fan is set to “ON” instead of “AUTO,” it will keep running even when your AC is off. Some thermostats also have a “FAN ONLY” mode that turns off the AC altogether but keeps hot air flowing through the system.

Air Filters Are Clogged or Incorrectly Sized

Anything that impedes airflow throughout your system can make it hard for your AC to circulate cool air around your home. There are a few different types of filter problems that can cause this issue. The most common is a clogged filter. If your filter hasn’t been changed in a while, it’s probably loaded with grime and dust. You can also run into problems if you use an overly efficient filter meant for a system with a stronger blower motor. If your filter’s MERV rating is higher than the manufacturer recommends, you can have problems. Usually, if your filter is obstructing airflow, you’ll notice that the air coming through your vents is both warmer and slower than usual.

Evaporator Coils Are Dirty

The evaporator coils in your HVAC unit are meant to absorb heat from the air and expel it outside your house. However, these coils can get coated with dust over time. When this happens, temperature transfer is less efficient. Your coils might struggle to pull heat out of your air, so your treated air feels warmer overall. Fortunately, this problem is quick and easy to fix. A professional maintenance visit can get your AC blowing cool air again.

Refrigerant Is Leaking

Refrigerant is a special liquid that can absorb heat and easily transition between liquid and gaseous states. It’s an essential part of the cooling cycle that helps keep your home comfortable. Usually, refrigerant is supposed to be in a closed system where it cannot evaporate or spill. However, a crack or a poor fitting can cause small amounts of refrigerant to escape. When this happens, your AC can no longer cool air. To solve this problem, you’ll need to have the leaky spot patched and refill your system with refrigerant.

Ductwork in Your House Is Leaking

If the air from only one of your vents is warm, your ductwork is probably the source of the heat. AC ducts run through uncooled parts of the home, like the attic or walls. In many cases, ducts develop holes due to rodents or fittings that gradually loosen over time. When a gap develops, cold air escapes from your duct, and hot air gets pulled in. In some cases, leaky ductwork can also cause strange-smelling or dusty air. Depending on how bad the leak is, this problem can be solved by either patching or replacing the duct.

The Compressor Is Broken

Your AC compressor helps refrigerant cycle through your system and expel heat properly. However, this complex machinery can fail over time. One of the early warning signs of a failing compressor is often warm air from the duct. Other potential signs include strange noises or a vibrating AC system. Typically, a broken compressor will need to be replaced if you want cool air.

If your AC is blowing hot air, turn to AirDepot. Our team of experts can diagnose the problem and recommend effective ways to fix it. In addition to AC repairs, we also offer a variety of other HVAC repairs, maintenance, and installations throughout the Cypress area. To learn more about AirDepot‘s services, contact us now.

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