Common Air Conditioning Odors And Their Causes

Air conditioning falls under the category of basic necessities (like food, shelter, and water do) given how important it is in a home in the present era. However, unlike most other necessities, air conditioners require maintenance and if not kept up with. Luckily, air conditioning systems typically give off warning signs when something is not right – poor air flow, warm air instead of cold, buzzing or other odd noises, and smells.

The following are some of the common smells that you might experience when something is wrong with your air conditioner, along with the likely culprit.

  1. Musty or Mildew Smell

This is a result of excessive humidity in your AC system along with the presence of mold or mildew in the ducts, clogged drain lines, or stagnant water in the drip pan. To solve the problem of this particular smell, you usually do not need help from expert. Check where the drip pan or wherever the AC releases the moisture pulled from the air for standing water or poor drainage. Also check the drain pipe – if it is dry, then there is likely a clog somewhere. Be sure to change all of the intake filters and continue to do so regularly. If your home is prone to humidity, install a humidifier in one of the main rooms to help pull moisture from the air and lighten the burden placed on your air conditioning system. If the smell persists, then your duct work may need a thorough cleaning. If you have never done this before, it is recommended to give us a call to ensure that no damage befalls your duct work or system.

  1. Dirty Socks Smell

Dirty Sock Syndrome is an actual “illness” that can affect your air conditioning system. The dirty socks smell (or gym bag, work boot, 3 day pile of wet laundry smell) is usually a product of mildew somewhere in your system. It could be in the duct work or around the evaporator coil.  Like the above smell, it is typically the cause of high humidity in the home or clogged drain pipes only stage of mildew is long past changing filters to resolve the issue. This will require an in-depth cleaning of your system.

  1. Cigarette Smoke

You guessed it – this smell is caused by of the presence of tobacco smoke residue in your AC system. Even if the smoker uses a designated room or part of the house for their smoking habit, the smoke can and will inhibit the air conditioning system and be filtered to the rest of the home. Change the filters more often and encourage the smoker to some only outdoors. At a minimum, better ventilate the areas where smoking is occurring by opening a window and using a fan to help circulate the air.

  1. Acetone

The scent of acetone, or nail polish remover, is an indication that you have a refrigerant leak in your system. A refrigerant leak can not only be disastrous for the efficiency of the system, but also your health. It poses serious health hazards so if you smell this odor in your air conditioning system then turn off the system immediately and get help from an expert.

  1. Rotten Eggs

This will only be a concern for residents or commercial offices who have gas-drive AC units. The smell of rotten eggs is a common description used when there is a gas leak. If you smell this in your house and you’re sure that it is coming from the air conditioning system, then immediately call a professional for help. Also, open the windows and turn off the appliances to avoid any spark that can result in an explosion, then wait outside for assistance to arrive.

  1. Burning Smell

In Florida, this smell is typically not a concern. You may experience a burning smell after turning on your systems heater after it is dormant for the majority of the year. When you don’t use your heater for a long period of time dust can settle on the heating coils. When you do start using it the dust gets burned off, resulting in a burning smell. The smell will eventually dissipate and fade away.

However, if you have been running your heater for the last 24 hours and the smell has already dissipated, or you never experienced it and you now are, then the smell could be an indication of overuse. When parts are dormant and do not receive regular maintenance, they can wear out from lack of use (just like a tool in your garage that never gets used may rust). It can also be a sign of a bad or malfunctioning compressor. If you smell burning several hours after the heater is in use, then turn off your unit and contact us to evaluate your system.

  1. Rotting Carcass

Sounds gross and the smell itself can be really disturbing and you can’t help but notice it. As the name shows, this smell is due to a bird, mouse, squirrel, or other creature dying after getting caught somewhere in your system. So, if there is a rancid, rotting smell and no other indication to its cause, you should turn off your air conditioner and contact an AC repairman. A decomposing body of a small mammal can be very harmful to your health and you don’t want your AC system to circulate it through your home.