Where Are Those Air Conditioner Smells Coming From?

image of homeowner plugging nose due to bad air conditioner smell

An air-conditioned room should smell normal. This means that you should not smell anything distinct around your house at all. Turning on your air conditioning system would lead to the rush of cold air in the room. This shouldn’t be accompanied by any air conditioner problems such as strange AC noises or odd, or offensive scents. When you notice your air conditioner emits a stench, it could be pointing to a problem that should be checked right away. Determine the culprit behind the air conditioner smells and what you can do about it.

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What Causes That Air Conditioner Smell?

This article includes a discussion on the various odors your AC unit might be producing and the reasons behind them.

Mold Smell From Air Conditioner

image of mold that was on air conditioner

The most common stench in homes that have air conditioners is the dingy mold smell. The musty odor is typically caused by the built-up moisture in the ducts, drain pan, or drip lines. This water and the ambient temperature create the perfect environment for mold, mildew, and fungus to grow. As a result, an unpleasant smell permeates throughout your house.
The stale smell of the air can also be because your air conditioner has clogged filters. Suppose you live in an area with high humidity and temperatures. In that case, moisture accumulation in the air filters is not uncommon, especially if the unit hasn’t been used for quite some time. This will lead to stale air filling the room when you switch your cooling system on.

Solution: Empty the drain pan at regular intervals. If the smell doesn’t go away, contact a reliable HVAC technician to inspect your air conditioner, including the ducts and lines. If water accumulation is present in your central AC system, it likely has a leak as well. Have your central air conditioner checked to find why the water is not draining correctly. Annual air conditioner maintenance is needed to ensure this problem does not happen again or at all in the first place.

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Air Conditioning Unit Smells Like Cigarette Smoke

If an occupant in your house smokes tobacco, it is likely that the air conditioning system absorbs its particles and gets trapped in the filter. However, whenever you turn on your system, these particles might become loose and mix in with the conditioned air. They get released through the vents with the cool air, and this could be why you smell smoke even though no one is smoking tobacco inside.

Solution: Smoke next to open windows. Better yet, step outside when smoking. Remember to clean or replace the air filter at least once a month as well. Wipe off any dust and dirt from your air conditioner’s surface every 7 to 14 days. Schedule your air conditioning maintenance during spring as well. Don’t forget to have your system maintained at least once a year.

Burning Smell Coming From Your Air Conditioner

image of air conditioner electrical wiresA burning smell spreading throughout your home might be because a component of your air conditioner is burning. It could be a faulty cable, a wire, or a motor. Other times, it could be because your air conditioner hasn’t been used for a long time. When the accumulated dust in it is suddenly exposed to high temperatures, a burning smell could ensue. There is no need to worry as the smell should dissipate soon. If it doesn’t, switch off your air conditioner and contact your local HVAC technician immediately.

Solution: Never conduct a DIY repair on an air conditioning system that is emitting a burning smell. Consult a professional HVAC contractor to assist you with the burning smell issue.

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Air Conditioner Smells Like Rotten Egg

A rotten egg smell coming from your air conditioner is probably because there is a decomposing animal inside it. When a body decomposes, it releases gases that smell rotten and foul. A small animal, such as a bird, reptile, or rodent, might have gotten inside your air conditioner or the ducts. It could’ve died before it could find its way out, so there is a rotten egg smell permeating throughout your house.

Solution: Locate the dead animal in your air conditioner or ductwork. Carefully remove and sanitize it. Ensure that all organic matters are eliminated. If it is in a hard-to-reach area or the task is too difficult, call an HVAC expert right away. They will conduct the necessary things to ensure that your cooling system is properly checked, cleaned, sanitized, and pest-proofed.

Air Conditioner Gas Odor

Methyl mercaptan depicting natural gas leakA gas smell from your air conditioner should never be ignored. This is because your system could be leaking gas. The gas doesn’t have any odor, but gas manufacturers mix methyl mercaptan with it. This chemical has a rotten cabbage-like smell. If you smell it around your house, it serves as a warning that a gas leak is currently happening.

Methyl mercaptan is an irritant. Exposure can cause eye and skin irritations, dizziness, headaches, nausea, and upper respiratory tract problems. Being exposed to it for too long can lead to coma or death.

Solution: When your air conditioner is leaking gas, turn off the gas supply right away. Allow proper air ventilation by opening all windows and doors. Evacuate your house, then call an HVAC technician immediately. Make sure not to light up anything while the smell of gas lingers in your home. Otherwise, the gas could ignite, and you’ll have worse problems in your hands.

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An air conditioning system can emit different smells because of various reasons. Some of them are harmless for the most part. However, some smells should never be ignored as they can signal a dangerous or potentially fatal issue. There are odors that can be removed with basic cleanings and filter replacements. On the other hand, some need a professional HVAC technician to look into them right away.

Never ignore any smell that your cooling unit produces. The problem should be fixed as soon as possible to avoid any health issues and expensive repairs or premature air conditioner replacements in the future.

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Call Townsend Energy For All Of Your HVAC Requirements

te logoWhen you need superior heating and cooling services in Northeastern Massachusetts, Southern New Hampshire, and Maine, make sure that you call Townsend Energy. We have the best professionally certified and highly trained technicians for all your HVAC needs, including boiler repair, air conditioner tune-ups, furnace replacements, and mini-split installations. All our friendly techs have the right skills, experience, and knowledge to ensure you receive accurate and prompt HVAC services at all times.

Our company assures you that we offer highly competitive HVAC service prices. We can improve your home’s comfort, indoor air quality, and efficiency through our maintenance services. If you need to repair or replace your system, we can recommend the best solution that fits your needs and budget. All our works are backed with a guarantee. Schedule a service appointment and call Townsend Energy today. We provide free, in-home estimates.

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