Why Is My Air Conditioner Blowing Hot Air?

 Picture this: It’s a hot day, you’ve spent the last few hours in the garden, and you can’t wait to walk into your cool home and relax. Upon entering your home you’re greeted by…warm air – yikes.  

Before you panic (or start sweating more), check out Crystal Heating & Cooling’s most common causes for your air conditioner blowing hot air, you may even be able to diagnose and fix minor issues on your own! 

  

1. Your AC Unit is Frozen

This is one of the most common causes of air conditioners blowing warm or hot air.  Just like your freezer can get a build of ice and stop working, air conditioners are also known to freeze!  This happens because the inside has frozen into a block of ice. 

The reason for the warm air blowing out of your unit is because the evaporator coil that helps create the cool air actually freezes which blocks the cool air from flowing into your home. Instead, the warm air from the AC motor is pushed into your home by the fan (of course, so long as the fan isn’t frozen too). To fix this issue try turning it off and letting it thaw. After about an hour or two, it should be safe to turn back on. If it freezes again, you should contact a local air conditioning repair company, such as Crystal Heating and Cooling, to take a look at it. 

 2. The Breaker Switch Has Blown

As with any appliance that requires power, your A/C unit has a power supply, which also has an on/off switch that can be tripped by a bad breaker. Without power, the unit simply won’t turn on. Breakers often flip off when there is a power overload as a safety precaution. 

To prevent this from happening, consult an electrician to ensure your breaker can handle the current draw of your unit. The fix for this issue is quite simple. Just flip the breaker back to the “on” position. If that does not work, contact an electrician.  

 

3. Incorrect Thermostat Settings

As silly as it seems, it’s actually quite common for homeowners to forget that they have to switch their thermostat from “warm” to “cool”. It’s important to also make sure the unit’s temperature is not set too high or on auto. Also, try to remember that just because your A/C is “on” doesn’t mean it is working – in some models, the “on” function means that the fan is on and circulating air, regardless of if the air is warm or cool. 

Make a note to yourself before the warmer months come to turn your A/C unit on “cool” mode. If you check your thermostat and the mode is set correctly, check the temperature and adjust it accordingly. 

 

 4. An Internal Malfunction

Like any appliance, many internal working functions begin the moment you hit the “on” switch, and your air conditioner is no different containing dozens of parts that all work together to efficiently cool your home.  Fortunately, most times we find it’s just one pesky part malfunctioning causing issues for the entire system, unfortunately, an internal malfunction is not one of the easier things for a homeowner to investigate, so it’s best to call us – especially since the last thing you need in the heat of the summer is to have warm air coming out of your A/C unit. 

 

 5. External Debris, Dirt, and Dust

If you’ve checked the internal elements of your AC and can’t find an obvious issue, it’s time to head outside to inspect the outdoor portion of your A/C unit. Check to see that your outdoor unit has the necessary 2ft of clearance on each side – this space helps to ensure the unit is able to “breathe” as it needs. Also check for any signs of debris like leaves, grass, or any other materials. Turn off the power to the unit, remove all debris you can see and reach and use a flashlight to inspect the inside of the unit checking for any debris as you go.  

 While you can definitely remove the larger debris by yourself, chances are if your outdoor unit was not covered properly that there is internal debris you cannot see, and it’s best to get an HVAC professional (like us!) to inspect and clean the unit safely and properly. 

 

 6. Your Air Filter is Dirty

When was the last time you changed or cleaned the air filter in your A/C unit? Most people never do until something goes wrong and it’s too late. 

Air filters get dirty and can block that clean cool air from entering your home. This blockage won’t clear up until you or a technician take it out and replace it. 

Although the filter alone won’t cause warm air to blow, it will contribute to the problem and reduce cooling effectiveness significantly – Are you guilty of not changing your air filters regularly? Sign up for our air filter subscription service! 

 

If you’ve checked for all of the causes mentioned above and you’re still finding that your air conditioning unit is blowing warm air, give Crystal Heating and Cooling a call and we will have you back up and running in no time. It’s no sweat!