Why Does My Air Conditioner Smell?

May 24, 2021

Louisville, KY, summers are sizzling hot and humid. Your air conditioner will regularly cycle to keep your home cool. If you notice a stinky or otherwise unpleasant smell when your air conditioner turns on, this isn’t normal. Read on to learn about four possible causes of a smelly air conditioner.

1. Clogged Condensate Drain

If you walk past the indoor unit of the air conditioner, you might notice a musty smell even when it’s not running. This is likely caused by a clog in the condensate drain. Bacteria, mold and mildew thrive in this dark, warm and wet environment. An annual spring tune-up and occasionally sanitizing with bleach or white vinegar eliminates the odor.

2. Dirty Air Filter

A dirty air filter is a common culprit of musty or stale smells from your air conditioner. Be sure to check the filter monthly. Once you see dirt on it, replace it.

3. Debris on Coil or Ducts

Debris on the evaporator coil or in your air ducts may release bad smells during cooling cycles. Bacteria may grow on the coil, and these bacteria release gas when they metabolize nutrients. Also, an animal may have gotten into your home’s ductwork, and this infestation can lead to foul odors as well.

4. Refrigerant Leak or Electrical Problem

If you notice a chloroform or strange sweet smell, your air conditioner could have a refrigerant leak. The odor may be accompanied by a hissing sound. Only an experienced HVAC technician can troubleshoot, diagnose and repair these leaks. If you detect an electrical or burning type of smell, your air conditioner may be overheating. Its capacitor could also have a problem.

Murphy Company Heating & Cooling is Louisville’s trusted air conditioning repair company. We also offer heating and cooling repairs, installation and maintenance services. Our indoor air quality and ductwork services keep your home efficient, healthy and comfortable. If you’re a Louisville area business owner, count on us for affordable commercial heating, ventilation and air conditioning services. For additional information on why your air conditioner smells, give us a call today.

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