How to Get Rid of a Bad Smell from an Air Conditioner: Spring Cleaning Your AC

Denver can get warm enough for an air conditioner by May, but what if you turn on your air conditioner and it stinks up your house?

Don’t just live with gross AC smells. Here’s what to do about various odors that can come out of your unit.

Why Does My Air Conditioner Smell?

AC units can smell for many reasons: disuse, friction from a mechanical issue, mold growing in the grills, an animal dying in your vents, and more. Some problems are minor; others are more serious. So, what do you do about different odors?

Fixing an Air Conditioner That Smells Bad When Turned On

The way you eliminate odors depends on what’s causing them. A general “bad” smell, like BO or dirty socks, could be solved by something as simple as cleaning your evaporator coil and unclogging a drain line. However, not every fix is that straightforward.

Here are some common AC odors and what to do when you smell them.

What to Do if Your Air Conditioner Smells Musty or Stale

If your AC smells stale the first time your turn it on after winter, check the coils for built-up dirt or dust that need cleaning. This smell should disappear with a quick wash and a few hours of running your unit.

A consistent musty smell usually indicates mold and mildew in your system, caused by everything from water damage to a leaking air conditioner to debris buildup in your vents. If your AC smells musty, empty your drain pan or check your drain line for clogs. Next, check your air filter for signs of mold and change it if necessary. Clean off your evaporator coil, keeping it clear of dirt, bacteria, and other grime.

Contact HVAC experts for air conditioner maintenance if the musty smell continues to come through your vents.

Mold and mildew also produce a variety of other scents, like vinegar, ammonia, and damp or even stale odors. If a professional confirms there’s mold in your ducts, schedule a duct cleaning to remove the problem.

What to Do if Your Air Conditioner Smells Like Rotten Eggs

A rotten egg smell likely isn’t a problem with your air conditioner but rather a natural gas leak in your home. If you have a natural gas hookup and smell rotten eggs in your home at any time, take action immediately: Shut off your gas, open a few windows for ventilation, and leave your home. Call your gas provider, likely Xcel Energy, to report the potential leak.

What to Do if Your Air Conditioner Smells Like Burning

If you smell burning from your AC unit, turn it off immediately. Call the fire department if the smell continues after you’ve turned your system off and you suspect something may still be actively burning.

A burning smell from any appliance is a bad sign that something’s seriously wrong. Any of the mechanical parts in your air conditioner could be generating friction and heat, or there could be an electrical problem. It’s possible that whatever’s causing the issue could start a fire if you leave the unit running without solving the problem.

To fix a burning air conditioner smell, contact AC professionals as soon as possible. We can diagnose and repair or replace your unit if necessary. If the problem persists, call an electrician to inspect your home wiring; the problem may be larger than your air conditioner.

What to Do if Your Air Conditioner Smells Like Chemicals

A “chemical” smell can cover a variety of odors: a sweet chemical smell, paint thinner, car exhaust, or even skunk. Chemical odors usually indicate a refrigerant leak, which requires professional handling.

An experienced One Hour Heating & Air Conditioning of Denver technician can patch a leak and recharge your system with refrigerant. However, ACs installed before 2010 are more likely to run on dangerous and environmentally damaging refrigerants, like R-22 or Freon. If your air conditioner is on the older side and leaking refrigerant, discuss the option of AC replacement with your technician.

What to Do if Your Brand-New Air Conditioner Smells

Your new air conditioner may give off a plasticky smell the first few times you run it. The odor should fade as the unit runs. If you experience any of the above scents and your system is under warranty, contact the seller or manufacturer to see if they’ll cover repairs or send you a new unit.

Denver AC Repairs You Can Trust

Many air conditioner smells are symptoms of a more significant problem, and that means calling in the pros to have a look. Contact an expert technician from One Hour Heating & Air Conditioning of Denver to repair or, if necessary, replace your malfunctioning air conditioner. We can diagnose the problem and recommend the best action to fix it. When you notice an unpleasant odor, don’t hesitate. Call (303) 622-3401 or book online.