Air Conditioner Smells: 4 Causes of Rotten Egg Smell in AC System

Cause #1 Dirty Air Filter or Evaporator Coil

Sulfur from the air can sometimes accumulate in your air conditioning system, causing the rotten egg odor. Your air filter or evaporator coil may have a buildup of dust and debris with high concentrations of sulfur. Cleaning these parts will get rid of the sulfur, and get rid of any air conditioner smells.

Excess sulfur in the air is indicative of poor indoor air quality. High concentration of sulfur in the air may appear after forest fires, volcano eruptions, or ash fall. Use an air purifier to improve the indoor air quality, and use a mask to prevent inhaling sulfur, which can irritate the eyes, lungs, and throat.

Cause #2 Mold Buildup

Certain species of mold and mildew emit sulfur or rotten egg-like smells as they colonize moist spaces. Check for damp spots near your vents, as well as mold growing in your air conditioning system. Mold may also smell like dirty socks, clammy feet, sweat, or have a musty odor.

If your air conditioner smells slightly of rotten eggs, then you may not need to call your gas company after all! The culprit may be mold colonies growing in or around your vents, which a Luce Aircon HVAC technician can remove from your air conditioning unit for good. Removing the mold will refresh your smelly air conditioner.

Cause #3 Refrigerant Leak or Gas Leak

A refrigerant leak or a gas leak is a serious problem in your home. Refrigerant is originally odorless, but manufacturers include additives into the gas to emit a foul odor, alerting the household of a gas leak indoors. A refrigerant leak would smell like rotten eggs, as does natural gas. A natural gas leak can be fatal when not addressed immediately.

Upon the first notice of a rotten eggs smell, shut off all your appliances, and unplug them from the socket. Open all windows and entryways to disperse the gas, and evacuate the premises before calling your gas company to deal with the leak with an immediate inspection of your gas lines. Gas may have gotten into your vents, causing your air conditioner to smell bad.

Cause #4 Dead Animal

When organic matter decomposes, it releases sulfur into the air, causing a smell like rotten eggs to emit from the decaying flesh. If you live in an area surrounded by natural habitats, or vermin crawling around, then that rotten egg odor problem may be due to an animal that died in your vents.

This is a common cause of central air conditioner smells as rodents or other vermin crawl through the centralized ventilation system, and eventually die within the air vents. The decaying animal matter gives off the rotten egg smell, which is transported through the house via the central air conditioner.

How to Remove the Rotten Egg Smell from Your AC Unit

Consistent Cleaning

Regular and routine cleaning of your air conditioning unit will remove debris that has accumulated in your cooling system. This will prevent an air conditioner from smelling like rotten eggs, and clear the filter from dust as well. This will also keep your air conditioning system functioning in good condition as the parts are able to work well.

Consistent deep cleaning is done by our technicians, who will clean every part of the air conditioning unit - including parts you can't clean yourself! A chemical wash will refresh and reinforce the different components of your air conditioning system, so you can continue to enjoy the cool feeling for a long time.

Maintenance and Upkeep

Your air conditioning unit will greatly benefit from maintenance and upkeep. Maintenance will be able to pinpoint weak spots in your HVAC system, and prevent your refrigerant lines from breaking. Our Luce Aircon technicians can also diagnose, repair, and reinforce any issues with your air conditioner.

House Inspection

You should be doing a house inspection once every year to make sure your gas supply and water lines are in good condition. This will prevent gas leaking through your vents, and water from creating moist environments for mold to thrive in; thus, preventing rotten egg smells from your air conditioner.

Keeping Your AC Unit Clean

Schedule to clean and maintain your HVAC system with us, and trust in our technicians that will be able to provide the best upkeep services to keep your air conditioner smelling fresh and clean always! We clean, diagnose, and repair air conditioners of various models and brands across Singapore.

‍

Check out our article on why ac smells like pee!