What Is Causing That Air Conditioner Smell?

image of a homeowner plugging nose due to air conditioning unit smells

The air that an air conditioner produces should not be accompanied by a smell. However, your air conditioner may sometimes produce a strange, unpleasant, or offensive odor. If this is the case, it is a clear sign that your air conditioner is experiencing a problem, and an HVAC professional should check it out. Keep reading to learn about problematic air conditioner smells – what causes them, and what you can do to resolve this issue.

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What Is Causing That Air Conditioner Smell?

This article discusses several air conditioner smells and their causes.

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Air Conditioning Unit Has a Moldy Smell

image of mold on air conditioner

One of the most commonly reported odors that homeowners encounter is a musty mold-like smell. This can usually be traced to the water buildup in the drip lines, ducts, or drain pan. The moisture and indoor temperature create a space where fungus, mildew, or mold can grow and thrive. This causes a dingy smell to permeate your home.

The stale air in your home can also point to dirty air filters. If your region is hot and humid, water can accumulate in the cooling unit’s air filters. This typically occurs when you haven’t switched on your system for some time. When you turn it on again, this results in stale air circulating throughout your home.

Solution: Make sure the drain pan is emptied at regular intervals. If the smell persists, contact an HVAC professional to examine your air conditioner, ducts, and lines. Water buildup in your central AC unit can also indicate a leak. You should have your system assessed to find the reason the water isn’t draining correctly. Remember that an annual air conditioner tune-up is crucial to ensure these problems do not occur in the first place. 

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Related Article: Best Ways To Prevent Air Conditioner Mold

Air Conditioner Produces a Burning Smell

image of air conditioner wires that are producing a burning smell

A burning odor permeating your home can be due to an AC part that’s actually burning. A defective wire, cable, or motor can be the reason. Sometimes, the burning odor is because the air conditioner hasn’t been switched on for a long time. When you turn it on again, the dust buildup in the unit is exposed to high temperatures, resulting in a burning odor. Don’t worry because the smell will dissipate soon. If it doesn’t, turn off the system immediately and contact an HVAC professional.

Solution: Do not conduct a do-it-yourself repair on a cooling unit producing a burning smell. Hire an expert HVAC technician to help you instead.

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Air Conditioner Produces a Cigarette Smoke Odor

If an occupant in your home smokes tobacco, the air conditioner will suck in the smoke particles that can get trapped in the air filter. This will occur each time someone smokes indoors. When you switch on your air conditioning, the smoke particles can become loose and mix with the cold air. They then escape through the vents, and you’ll smell cigarette smoke around your home even if no one is smoking.

Solution: The next time you smoke in your home, open a window to reduce the cigarette smell. Consider going out of the house to smoke. Remember to clean your air conditioner once a week or every two weeks. Wipe the dirt and particles on the unit’s surface. Ensure that the air conditioner receives annual maintenance as well. The recommendation is that you get your unit maintained every spring.

Related Article: How Does An Air Conditioner Tune-up Save Me Money?

Rotten Egg Smell Coming From the Cooling System

A dead animal in your air conditioner can cause a rotten egg smell to permeate your home. The decomposition of a body causes the release of foul-smelling odors. Birds, rodents, and other small critters may have gotten inside your air conditioner and died. This causes the rotten egg smell to circulate in your home.

Solution: Search for the dead animal in your air conditioner and ductwork. The dead animal should be carefully removed. The system should also be sanitized to ensure that all traces are removed. Call a dependable HVAC technician to help you if the dead animal is in a hard-to-reach spot. They have the correct tools and years of experience to examine, clean, and sanitize your air conditioner. They will also make sure that your system is pest-proof so it doesn’t reoccur.

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Air Conditioner Gas Smell

Never ignore a gas smell because it may be from a gas leak. The gas shouldn’t have any scent, so manufacturers add methyl mercaptan. This substance emits a rotten cabbage odor that warns you if gas is leaking. Remember that methyl mercaptan is an irritant. Exposure can result in dizziness, headaches, skin and eye irritations, nausea, and respiratory problems. It can also cause death if exposed for prolonged periods.

Solution: Switch off the gas supply as soon as you suspect a gas leak. Open the windows to make sure your home is adequately ventilated. Evacuate your home immediately and call a dependable HVAC technician right away. Gas is easy to ignite, so never light up anything while the gas smell lingers.

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A malfunctioning air conditioner can cause it to emit different odors. Some smells are harmless, but others shouldn’t be ignored. The smell can indicate a few severe and potentially lethal issues. Cleaning and replacing the filters can remove some odors, while others need an HVAC professional to check them.

Don’t neglect any smells your cooling system emits. In most situations, resolving the issue immediately will prevent health problems. It also means you don’t have to spend money on costly repairs or replacements in the future.

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Call Van Varick & Sons For All Your HVAC Requirements

Van Varick & Sons provides top-quality HVAC services in Northern New Jersey. Our professionally certified technicians can assist you with all your heating and cooling needs, such as boiler installations, mini-split replacements, and air conditioner maintenance, to name a few. All our friendly techs have years of experience, extensive skills, and knowledge to service any HVAC make and model safely and correctly.

Our company guarantees one of the region’s most affordable HVAC service costs. We can assist in improving your home’s indoor air quality, comfort, and energy efficiency with our tune-up services. Our techs can suggest the best and most budget-friendly solutions if your home requires an HVAC repair or replacement system. To schedule a service appointment, give Van Varick & Sons a call today. We offer free, in-home estimates.

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