Why Your AC Smells Funny: Types of Odors Explained

Common Types of AC Smells

One of the most common odors is a dusty smell, and it often occurs at the beginning of air conditioning season when the system hasn’t been used for a while. As long as it goes away in a few days, it’s generally nothing to worry about. It is just the dust that’s accumulated in the system.



However, many other odors do require your attention. Here are some that you might notice.

Rotten Eggs

If you notice the sulfur smell you associate with rotten eggs, you may have a gas leak. This can be serious and requires immediate action. Shut off your gas, get everyone out of the building, and call 911. Even a minor exposure to gas is a health hazard. Continued exposure can render you unconscious and even kill you.

Burning

As with the rotten egg odor, this is an emergency situation. Shut off your HVAC system, call 911, and evacuate. Possible causes include an overheated motor, frayed wiring, and other mechanical issues, but the first priority is to learn whether there is a fire and get it extinguished.

Dirty Feet

If your AC is emanating an odor reminiscent of a basket full of dirty sweat socks, there’s a good chance you have bacteria growing on your evaporator coils. This is a performance issue for the evaporator as well as an obnoxious odor for you. You’ll need to contact an HVAC professional to have those coils cleaned and sanitized.

Gunpowder

Some people describe this smell as resembling automotive exhaust. A common cause is a fluid leak where the fluid is dripping onto the motor or some other hot component. This sort of fume may be toxic, and you will need an HVAC pro to take care of it right away.

Mold

A musky, damp odor means you probably have mold or mildew somewhere in your system’s interior. There is a lot of condensation in a working AC, and if the moisture doesn’t properly drain, it can escape into the ducts and allow mold to form. Mold is unhealthy for respiration but is not a threat to most people in the very short run. Unless you have someone with asthma or allergies who is particularly sensitive, you can continue to run your system until your appointment with your HVAC professional. It’s still important to locate and remove the mold quickly to safeguard everyone’s health.

Cigarettes

If you smell cigarettes, the source of the odor is, in fact, tobacco. Someone has been smoking near the unit or the vents, and residue has built up inside the air conditioner. The source could also be someone smoking near an outside vent. Put a stop to the smoking, and the odor will diminish.

Garbage

If your system has a garbage smell that makes you think something crawled inside and died, that’s probably exactly what happened. Critters like mice, rats, and raccoons will often take shelter when it’s cold, and they don’t always make it out before the weather warms. Shut off the AC, open your windows, and call an HVAC pro or a pest control expert.

Reasons for Smelly Air Conditioners

Some of the reasons are the ones described above, including gas leaks, fluid leaks, overheated motors, condenser coils dirty with bacteria, and even dead animals in the system. However, many are problems that can be addressed by routine maintenance. For example, as the AC runs, water falls into the drain pan directly under the evaporator coils. Sooner or later, the pan needs to be replaced to prevent mold growth. There’s also a condensate line that runs from the pan into the landscaping and can accumulate buildup if it’s not kept clear. In addition, as the unit absorbs indoor air, removes humidity, cools the air, and pumps the air via the vents, the filters have to be clean for this to happen properly. Sometimes, the root cause is as simple as a clogged filter.

Can I Fix the Scents Myself?

It’s best to have a professional diagnose and correct the problem. However, there are some things you can do to mitigate the odor while you’re waiting for your HVAC expert to visit. The first step is to clean or replace any filters that haven’t been attended to for a while. Also, you can check to see whether the drain pan is full. If so, empty it, and it’s also a good idea to clean it with soap and water to get rid of any trace of mold that may have started.

When to Call HVAC Professionals

If you smell rotten eggs or something burning, call 911 and get the emergency problem taken care of first. For other odors, call an HVAC professional and get the issue resolved as quickly as possible. Even if you’ve changed filters and emptied the drain pain and the odor has diminished, you still should call and find out whether there’s a continuing problem.

Of course, the best time for HVAC service is before any odor occurs. Regular maintenance, including inspection, tune-ups, and balancing, will extend the life of your system and reduce the probability that smelly issues will arise.

Reach out to 1 Source Mechanical Today for your Commercial HVAC Needs!

1 Source Mechanical is the expert to call, not only if you have an AC odor but also if you need any kind of HVAC work, including installation, maintenance, or major or minor repair. We are the premier HVAC company for work anywhere in the greater Chicago area. No matter what your HVAC requirements are, contact us today and partner with the Chicagoland leader in HVAC services.