What Would Cause My Air Conditioner to Smell?

Odors

• Common problem smells to come from air conditioner include the dank, earthy odor of mold, which is what gives damp basements their characteristic musty odor. Other smells you might notice coming from your air conditioner are strong cooking odors, like powerful spices even though the meal you used them for is just a memory. Your air conditioner could also blow in the scent of smoke, either from cigarettes or a mishap with popcorn left too long in the microwave.

Causes

• The cause of smells coming from your air conditioner is a problem known as odoriferous coil. It can occur when the condenser pan in your air conditioning unit does not drain properly. The buildup of water encourages mold growth on and around the condenser coil. The scent of the mold is blown from the air conditioning unit into your home from the air ducts. Strong odors can coat the condenser coil. If you cook with bold spices or someone smoked in your home, the odor could be on the coil and, just like the smell of mold, blow back into your house.

Solutions

• Cleaning the coil gets rid of the issue of odoriferous coil. Start by pouring 1/4 cup of household liquid bleach into a gallon of water, and mix thoroughly. Using a sponge, wipe down the coil with the solution. Wipe away any visible mold growth, whether it is on the coil or not. Once the coil is clean, wipe it down with clear water. If the condenser pan is not draining properly, have it repaired or mold growth could return and bring with it the musty smell.

Considerations

• When cleaning with bleach, wear gloves to protect your hands because it can irritate your hands. If you clean the condenser coil and, a day later, you can still smell the odd odor when your air conditioner runs, change out all the air filters in your home. They can absorb strong odors and, when your air conditioner runs, they recirculate the smells into your home. Changing them on a regular basis will increase your unit's effectiveness and reduce the chance of smells lingering in your house.