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Kilowatt Heating, Air Conditioning and Electrical Blog

Strange Smells from the AC? Here Are Some of the Possibilities

HVACkidNobody wants a smelly appliance in their house. But a smelly air conditioner… that’s not something people expect to happen. But it does! You may notice odd smells wafting from the room vents in your house when you have your air conditioning system running. These smells can indicate simple, innocuous problems. Or they could indicate a need for Los Angeles, CA air conditioning repair on the double. We’ll go over some of the more common bad AC odors, what they may mean, and what to do about them.

Stinky Socks

This is one of the most frequent bad smells to come from an air conditioner. In fact, it’s so common it has its own name: “Dirty Sock Syndrome.” This might be an issue with stagnant water in the condensate pan of the air conditioner. If the condensate drain is blocked, the water collected in the pan can create this unpleasantly, mildewy smell. Repair technicians can clean out the drain and the pan to fix it.

But Dirty Sock Syndrome is more often a problem with mold growing along the condensate coils of the AC. Not only does this spread the stinky sock odor around the house, it causes the air conditioner to lose energy efficiency. Call for a technician to clean off the coils using special chemicals. (Please don’t try to do this yourself, as you may damage the coils.)

Cigarette Smoke

If someone in your house smokes, the residue from the cigarette fumes can get caught in the air conditioner’s filter. Usually you can fix this problem by changing the filter more often. If you usually change the filter once every three months, switch to changing it once a month.

Acrid Smells

A burning smell from the AC vents may cause you a jolt of panic. Is something on fire? It’s probably not that bad—but it is something to be concerned about, because it’s probably a motor burning out. An electrical fire is still a possibility, so shut off the air conditioner and call for HVAC repair experts right away to investigate the burning smell.

Rotten Eggs

This is a big warning sign you have a gas leak in the house that’s occurring near the return air ducts for the air conditioner. Carbon monoxide doesn’t have a natural odor, but natural gas companies add a chemical to it that creates a rotten egg smell to alert homeowners to a leak. If you notice the rotten egg smell and your CO detectors go off, leave the house immediately. Call the gas company first. Once any danger is past, you’ll need professional HVAC assistance.

Other Rotten Smells

If the odor from the AC is a more non-descript smell of rotting, like an overfull dumpster, then you may have a dead animal such as a bird or rodent in the ductwork. Yes, this is job you’ll want an HVAC specialist to take care of. Ventilation professionals can remove the animal and then handle repairs to the ducts. (Animals in ductwork are a common cause of duct leaks.)

Kilowatt Heating, Air Conditioning and Electrical serves Los Angeles and the San Fernando Valley. Reach out to us when you need late-summer air conditioning repairs.

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