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What's That Smell? Possible Causes Of The Strange Odors Coming From Your Central Air Conditioning System

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While your central air conditioner is running, you may have started noticing an odd smell coming from the vents. Below are possible causes of three types of strange odors that may be coming from your air conditioning unit or ductwork. 

Stale And Musty Odor

If you detect a stale, musty odor in your home's air, there are two possible causes. First, if you have recently turned your air on for the first time after shutting down the unit for the winter, dust may have collected inside the compressor and it is circulating through the vents.

The second possible cause is that mildew has grown on the filter. Try changing the filter if you have not already done so for the season. If this does not help, you may have mildew growing inside the unit that should be cleaned out by a professional.

Dirty Sock Smell

Another unusual odor you may be experiencing is the smell of dirty socks that have gotten wet and left to fester for a while. While the cause is not dirty socks inside your unit or ducts, the festering part is possibly causing the odd smell.

When mildew, mold, and bacteria start to grow inside the unit, it is forced into your ducts. When you turn on the heater, the extra warmth helps the germs and fungi grow. When you turn on the air conditioner, you then force them into your home's air.

If you suspect your home has dirty sock syndrome, you should have an HVAC professional look at your air conditioning system. Depending on the extent of growth, it may need to be cleaned or parts may need to be replaced.

Burnt Rubber Or Metal

If you smell something burning every time your air conditioner's compressor kicks on, such as the smell of burnt rubber or metal, you may have a serious issue with the motor or wiring. A burning rubber smell could indicate that the gaskets have come into contact with the compressor and are melting.

A burnt wire odor could indicate a short in the unit. You should have someone inspect the electrical system of the air conditioner so repairs can be made before the short burns up the motor or starts an electrical fire.

If you detect any of the above odors, you may want to have a professional inspect your unit and ductwork so you can be certain of the cause. Contact a contractor who specializes in residential air conditioning repair--such as one from AC Pros of Florida Inc--to diagnose the problem and offer suggestions on how to fix it.