Why is My AC Blowing Hot Air?

by George Karonis

It’s never a good sign when your AC starts blowing hot air. AC is supposed to keep you and your home cool, which it can’t do if it is releasing hot air into your home rather than cool air. In this blog post, we discuss the reasons why your AC is blowing hot air and how to fix the problem. Also, we’ll introduce an effective alternative to AC.

Reasons why your AC is blowing hot air

  • Thermostat setting - Starting with the most obvious fix is always a good place to start. Often, the problem could be as simple as your thermostat is set to heat rather than cool. If that’s the case, just switch the thermostat setting and you’ll be good to go.
  • Outdoor AC unit is blocked - Debris or overgrown plants can clog your AC unit and prevent it from properly functioning. Always make sure that your system is free from any obstructions. Check the outside of the AC unit and clear everything away from it.
  • Clogged air filters - Air filters trap pathogens which are particles in the air to ensure that the air you’re breathing is clean. Over time, the filters become saturated with dust and other particulate matter, clogging up the AC system. Check and clean your air filters about every 30 to 90 days to make sure they are clear and your AC is operating properly.
  • Duct leak - If you have a leak in your home’s ductwork, the cold air from the AC may mix with warm air and it may feel like your AC is blowing cold air. Ductwork leaks should be fixed by an HVAC professional.
  • Refrigerant leak - Refrigerant is essential for the AC’s ability to produce cold air. If there is a refrigerant leak, the AC is unable to create cold air to blow and may instead blow warm air. Check to see if the evaporator coils are frosted over, this is a good sign that you have a refrigerant leak and you should contact an HVAC professional to fix it.
  • Clogged condensate line - If you’ve ever been around the outside of your AC unit, you’ve probably seen the condensate from the AC. This is completely normal and a necessary part of the proper operation of your unit. The line that carries condensate outside can become clogged and interfere with the operation of your unit.
  • Clogged evaporator coils - Evaporator coils allow for the hot air to be cooled in the AC system. The coils can become clogged or dirty and result in a malfunctioning AC blowing warm air.
  • Old AC unit - ACs don’t last forever. If you’ve had your AC for decades, it may be time to replace it.

Whole House Fan: An Alternative To AC
Air conditioners are not the only solution to a hot and humid home. Whole house fans are a less expensive, greener alternative to AC. They work by cycling hot, polluted air out of the house and pulling in fresh, cooler air. They are particularly effective at nighttime and can be used to supplement an AC or replace an AC to decrease energy costs and reduce your household’s carbon footprint. Check out wholehousefan.com to get yours today.

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