Where Are Those Air Conditioner Smells Coming From?

woman plugging nose from smelly air conditioner

Ideally, an air-conditioned room should smell… well, normal. Normal in the sense that there should not be any distinct smell at all. When you turn on the air conditioner and the rush of cool air fills the room, there shouldn’t be an unpleasant, strange, or offensive odor. If your air conditioner is producing a stench, it is a sure sign that something is up and should be checked immediately. Find out what types of air conditioner smells your AC unit is likely going to produce, what their causes are, and what you should do about it.

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What Is Causing That Air Conditioner Smell?

In this article, we discuss some causes for odors that your air conditioner may be emitting.

Air Conditioner Smells Like Mold

image of mold on an hvac air filter

A dingy smell that is reminiscent of the smell of mold is easily the most commonly reported scent among homeowners who have air conditioners. The musty smell can usually be traced to water that has accumulated in the drip lines, ducts, or drain pan. The moisture, along with ambient temperatures, creates an environment that is conducive for mildew, mold, or fungus to grow. These microorganisms are the reason for the unpleasant smell.

The staleness of the air can also be traced to dirty or clogged filters. If you happen to live in an area that experiences high temperatures and humidity, moisture can develop and accumulate in the air filters especially if you have not used the AC in a while. When you turn it on, the smell of the stale air will fill your room.

Solution: Try to empty the drain pan regularly. If this does not eliminate the smell, get in touch with an HVAC technician and have your air conditioner, ducts, and lines professionally inspected. If water accumulates in your system, it may have a leak as well, which means your central AC unit will benefit from a timely checkup to see what causes the water to drain improperly. It is important to note that an annual air conditioner tune-up is necessary to prevent these types of issues from occurring in the first place.

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Air Conditioner Smells Like Cigarette Smoke

If someone at home is a tobacco user, your air conditioning system will absorb the tobacco particles via the air filter. Each time you or someone at home smokes, smoke particles will be pulled into the air conditioning system and pushed through the filter. This should be all right for a while since the particles are simply trapped on the air filter. However, when you turn on the AC, the particles may be loosened and mix with the air that is released through the vents. As a result, you smell the cigarette smoke even when no one is smoking.

Solution: Try to smoke next to an open window to minimize the smell of the cigarettes or just simply step out for a few minutes to smoke outside. It is also important to clean or change the air filter every 30 days. Clean the AC unit once every week or two weeks to wipe off any dust and particles that may be present. Again, be sure to schedule air conditioner maintenance in the spring on an annual basis.

Burning Smell Coming From Your Air Conditioning Unit

image of air conditioner electrical wires

The smell of something burning may actually be a part or component burning. It could be a wire, a motor, or a cable that has become damaged. In some cases, such as when you have not used your AC unit for a long time, the burning smell may just be dust that is exposed to high temperatures. This should be temporary. However, if the smell lingers, turn off the air conditioner unit right away and call an HVAC technician immediately.

Solution: Never attempt to repair an AC unit that produces a burning smell. Ask a professional HVAC contractor for help instead.

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Rotten Egg Smell Coming From Air Conditioner

The smell of rotten eggs in your air conditioning system is likely due to a decomposing animal. This rotten, foul smell is the result of gases that a body produces when it begins to decompose. If small animals such as rodents, reptiles, or birds find their way inside your AC system and die inside it, the rotten egg smell is what you’ll get.

Solution: Find the dead animal in your air duct or system, remove it, and sanitize the area, removing all traces of the organic matter left behind. If the area is difficult to reach, call an HVAC technician right away. Also, be sure to have your cooling system checked, cleaned, and pest-proofed.

Air Conditioner Gas Odor

Methyl mercaptan depicting natural gas leakThis is an odor that you should never ignore. The smell of gas could likely be caused by actual gas leaking. Although gas itself does not have any odor, gas manufacturers added a chemical called methyl mercaptan to the mix. Methyl mercaptan is similar to the odor of rotten cabbage and is a warning that a serious issue is occurring – that is, a gas leak.

Methyl mercaptan is an irritant and can cause nausea, dizziness, headache, and problems with the upper respiratory tract. It can also irritate the eyes and skin. Prolonged exposure can also lead to coma or even death.

Solution: Leaking gas is a warning signal for you to turn off the gas supply immediately. Open the windows to allow ventilation, evacuate your home, and then call up your HVAC contractor right away. Try not to light up anything while you can still smell the gas because gas is easily ignited.

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Smells can emanate from an air conditioning system for a number of reasons, some of which are generally harmless. However, some odors should not be ignored because they usually point to a serious or potentially fatal problem. Some smells can be eliminated by simple cleanups and filter replacements but others need immediate attention from a professional HVAC technician. Do not ignore any odors that the AC system produces. In many cases, getting the problem resolved immediately will not only prevent health issues on your part but also help you avoid costly repairs or replacements in the future.

Call McAllister Energy For Superior Heating & Cooling Solutions

McAllister Energy

McAllister Energy offers high-quality HVAC services in Camden County, New Jersey. We hire only the best professionally certified HVAC technicians who conduct superior heating and cooling services. Some of our HVAC services include indoor air quality solutions, HVAC maintenance, heating and cooling installations, repairs, ductless systems, and much more. All our techs provide accurate HVAC services on time, every time.

Our company guarantees affordable heating and cooling service rates. Our maintenance services can increase your home’s comfort, energy efficiency, and cost-effectiveness. We can also provide you with a highly energy-efficient HVAC replacement system that fits your budget. Your satisfaction is important to us, so all our work comes with a guarantee. Book a service appointment with McAllister Energy today. We provide free, in-home estimates.

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