4 Reasons Why Your AC Unit Is Blowing Hot Air


When most people think of air conditioning, they imagine a brisk blast of cold air greeting them as they walk into the office in the morning or return home in the evening. What can you do if that cool blast is as warm as your coffee? There’s nothing more uncomfortable than a busted air conditioning unit that blows hot air. Luckily, you can often address this issue without an HVAC technician.

An Honest Mistake


Photo via Flickr by Texas Furniture San Antonio

Start by staying positive, and try not to jump to the conclusion that your air conditioner blows hot air because the unit is malfunctioning. One of the more common and most fixable air conditioning problems lies in your thermostat. One second you’re playing with the air conditioning settings try to get the temperature to drop that single, vital degree holding you back from a cool paradise, and the next you’re feel like you’re in a sauna. Always check your thermostat to make sure you haven’t switched your setting from “cool” or “auto” to “heat.” If you have, switch the setting back to air conditioning, and you’ll be cool in no time.

Dirty Coils

Once you’ve checked the thermostat, switch your attention to the HVAC air filters. If you haven’t been replacing your air filters every one to three months, you’ll likely end up with a dirty evaporator coil. Although air filters are easy to service on their own, you’ll have to call an HVAC technician to clean the evaporator coil. With any luck, you’ll realize the issue before the hardware becomes too damaged or needs a complete replacement.

Getting Technical


Photo via Flickr by michael_swan

Another reason your air conditioner blows hot air might stem from the unit’s compressor or condenser. Since these components reside in the air conditioner’s exterior unit, check to see if the power supply outside your home is working properly. If not, find the circuit breaker and switch the power back on. Without this power supply it’s impossible for your unit to blow cool air, but it can still blow warm air. If restarting the power doesn’t work, you may have a much larger problem on your hands.

Ice to Meet You

Air conditioning units can take a lot of wear and tear, as long as they have a steady supply of refrigerant. Without it, your HVAC system can’t condition the air. If you think you have a refrigerant problem, look for icy buildup on the inside and outside units or call a professional for a second opinion. The best way to prevent this from happening in the first place is to have annual or semiannual maintenance checks, when an HVAC tech can inspect the Puron or other sustainable refrigerant levels in your air conditioner.

When you say people are full of hot air, you don’t necessarily listen to what they have to say. When your home is full of hot air, however, listening to an expert is absolutely a good idea. Next time your air conditioning is blowing hot, run your own diagnostics before calling the professionals.