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Why Your AC Smells When You First Turn It On

ac smells | AC repair

When the day finally arrives to turn on your air conditioner for the first time this season, an unpleasant odor may be laced with the cool air. If you’re feeling grossed out, don’t worry—the smell usually dissipates after the first use. Still, proper AC maintenance before shutting down in the winter and again before restarting in the spring can prevent unpleasant odors.

Here’s a look at what’s happening if your air conditioner smells when first turned on:

Mold on the Evaporator Coil & Fins

Prolonged periods of disuse cause dirt, dust, and moisture to collect on the indoor evaporator coil. This creates an environment for mold to grow. As air passes over the evaporator coil and fins for the first time this season, it picks up the decaying odor created by the mold and carries it into your home.

To help prevent this odor, clean the evaporator fins with water and a few drops of mild detergent each fall. Repeat this cleaning technique again in the spring before turning on your AC for the first time.

Mildew on the Air Filter

Dust, hair, and moisture on the AC filter encourage mildew growth, which can cause a musty odor when the air conditioner runs. This is a likely reason why the air conditioner smells when first turned on if you don’t use forced-air heating in winter.

To help prevent this odor, clean or replace the filter in the spring.

Algae & Mold in the Drain Pan

Air conditioners generate condensate as they remove excess indoor humidity. This moisture drips into a drain pan, where mold and algae can form. This blocks the drain and can also generate an unpleasant odor when you run the AC for the first time.

To help prevent this odor, empty the drain pan before retiring the air conditioner for winter. A quick wash with diluted bleach in the spring eliminates all residual smells for a fresh start to the cooling season.

Have You Maintained Your AC Yet? Schedule Your Spring Tune-Up!

If your air conditioner smells when first turned on, try the above tips to eliminate bad odors. If the air still stinks after a day or two, call Arctic Air Conditioning for help. We provide valuable AC maintenance services that help you get the most from your system, whether you’re dealing with bad odors or not. To schedule services in New Jersey, please contact us today!

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