Why Does My Air Conditioner Smell Bad When Turned On?

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It’s not always easy to tell if you have a problem with your air conditioning unit. But one sign that does make it easy to know when there’s a possible issue is a foul odor.

Edelman, Inc. explains what can cause these odors and how you should handle them if this smelly summer problem should happen.

Why Does an Air Conditioner Smell Bad When Turned On?

If your air conditioning smells bad when turned on, the AC unit could be a problem. Sometimes, these issues require the help of a professional to fix. However, some odors are pretty standard and can be corrected quickly if you know what to do.

Below you’ll find some common reasons why the air conditioner smells terrible when turned on and how to handle them.

Musty, Moldy Smells

As a homeowner, you need to be aware of the causes behind the musty or stinky odor in your air conditioning system. If it smells funny when you turn it on, that might be a sign of mold, and it’s likely that mold or mildew is growing somewhere in the system. Mold commonly grows within the air ducts or the indoor unit’s evaporator coil.

This growth can be caused by a leaking or clogged AC. If water collects in the drain pan and cannot flow out of the system, it may contribute to mold growth.

  1. Turn off your air conditioner and open the access panel to inspect the drip pan.
  2. Remove standing water with a wet/dry vacuum, then clean the entire pan with a vinegar or bleach solution to kill the mold and stop it from regrowing.
  3. If the drain line is clogged, you may be able to clear it with your garden hose.
  4. Call your HVAC professional if you have trouble removing the condensate drain line and treat any mold growth you suspect within your air conditioner.

Odors from the House

A dirty air conditioner can produce an unpleasant smell, and you may notice the air conditioner smells like rotten eggs when turned on. The smell is because there are odor particles inside the household that get trapped on the air conditioner’s evaporator coil, which is located inside the indoor unit. Particles can travel through the air supply and into your air conditioner, causing smells like:

  • Cooking odors
  • Cleaners
  • Cigarette smoke
  • Pet hair
  • Air fresheners
  • Fumes

When particles settle here, they can release a smell every time you turn your HVAC system on. To control odors stemming from the home, change the filter regularly, which may be anywhere from one to 12 months, depending on your home’s model and air quality. Have the evaporator coil cleaned once per year – this service is usually performed during a cooling system maintenance tune-up.

Burning Smells

When a smelly air conditioner is turned on, the system may be running too hot. When electrical AC smells are present, it’s a sign that the components are overheating. Overheating can impact different parts such as circuit boards and fans, blower motors, compressors, etc.

If you notice this smell from your air conditioner, turn the system off, have your HVAC technician inspect it, and make repairs before further use to prevent causing more damage to the affected parts.

Air Conditioner Repairs

When you notice the air conditioner smells bad when turned on, check for simple solutions, like a dirty filter or drip pan. If you can’t fix the problem or suspect the odor is a sign of a more severe AC issue, call Edelman, Inc. for air conditioner repairs.

Contact Us Today!

If you are tired of dealing with a smelly air conditioner, you need professional assistance. When it comes to something as important as the comfort of your home, don’t trust just anyone with a Facebook page.

At Edelman, we let our clients do the talking for us. With 4.9/5 stars on Google, it is no question that we provide the premier HVAC services in the state. If you are ready to experience top-of-the-line service, contact us today!


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