During the warmer months, the A/C kicking on usually means a refreshing cool breeze blowing through the rooms of a home. If that breeze is accompanied by a funky, unpleasant odor wafting from the vents, then that breeze is less than welcome, and it’s usually a sign that something needs to be investigated and sorted out within the A/C. Rather than finding ways to cover up the smell, such as candles or wax warmers, it’s important to identify and address the cause of the smell, as it could be a sign of something more major taking place. Even if the smell can’t be pinned down, or sorted into these common categories, it’s better to have the offending odor checked out to make sure the A/C is running as it should and to rule out possible issues.

A Musty or Moist Smell

A musty or moist smell — not unlike a wet towel that’s been sitting out for too long — is usually a good indication of potential mold or mildew growth. This could be due to the A/C compressor becoming clogged, and not draining properly, causing moisture to accumulate in the compressor and grow stale. It also could be a sign of general moisture leaking into the air ducts — potentially from an unresolved plumbing issue — or it could be that the A/C filter has been used past its recommended replacement time, and the clogged filter is causing condensation to gather in the ducts.

No matter the cause, mildew, or mold growth are potential health hazards. Make sure to contact a professional to complete a thorough inspection, cleaning, and repairs as needed, to ensure no spores or bacteria are spread through the vents and airways.

A Burning or Gun Powder Smell

If there is a wiring malfunction, a mechanical issue, or a fluid leak, these all could create smells that are similar to burning or reminiscent of gunpowder. In all instances, these types of smells usually indicate that some part of the A/C itself is not functioning as it should, but that electricity is still connected to the worn-down part, which could lead to a more serious malfunction or potentially a fire. As such, it’s important that the home’s A/C unit is shut down and a professional contacted for an inspection and repair immediately.

A Rotten Egg Smell

This smell is perhaps the most unpleasant, and a mixed bag in terms of issues. First and foremost, it’s important to rule out that the smell is not a gas leak. If unsure about this possibility, it’s always better to play it safe, which means:

Avoid creating sparks or flames, and extinguish any immediately.

Open as many doors and windows as possible.

Turn off the gas supply, if you are able.

Evacuate the home, and contact the gas company.

If a gas leak can be ruled out, this leaves the unpleasant possibility of a rodent issue. It is possible that an animal has tried to make either the ducts or the A/C itself a new home, and instead, found itself trapped and passed away, leading to a highly displeasing, rotten odor. While it’s possible to tackle this, removing an animal’s carcass from either location is generally best left to professionals.

An Old Smoke/Stale Cigarette Smell

The culprit here is usually straightforward — the smell of old smoke or stale cigarettes generally comes from someone having smoked in the home — either at present or a previous tenant — and the smell becomes embedded in the ductwork. To remove the smell, a thorough cleaning of the air ducts and vents is required, which should eliminate the odor at its source.

All in all, most smells coming from an A/C should, at the least, warrant an inspection from a licensed professional. More often than not, the issue veers toward being potentially serious, and at the least, it provides peace of mind about exactly what is causing the odor, and how best to rectify the situation. If there is an offensive smell lingering from your A/C, or if you have additional questions about potential HVAC issues, give the experts at Duane Blanton Plumbing, Sewer, Heating & Cooling a call. Trained and licensed technicians with over 30 years of experience, the professionals at Duane Blanton Plumbing, Sewer, Heating & Cooling are thoroughly equipped to set your home A/C right. Give Duane Blanton Plumbing, Sewer, Heating & Cooling a call today at (815) 219-4323, or reach out online through their convenient online scheduling portal, and schedule with ease right from your computer or mobile browser.

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