9 Bad Air Conditioner Unit Smells & What To Do To Remove The Stench?

9 Bad Air Conditioner Unit Smells & What To Do To Remove The Stench?

What’s that horrible stench coming from the air conditioner? Just as important, how can you get rid of it?

To find out, consult this list of 9 common bad smells from your air conditioning, with solutions for each one.

1. Rotten Eggs

Beware. An air conditioner that smells like rotten eggs or sulphur almost always means one thing: there’s a gas leak in your house, which is getting into your ductwork. Natural gas is a hazardous substance. It can catch fire, explode, and/or reduce oxygen levels in the bloodstream with severe, often fatal, consequences.

WHAT TO DO: Turn off the gas supply if you can do so safely and have everyone leave the house. Then call 911 or your gas company to report the leak.

2. Dirty Socks

Dirty socks, funky feet, or “eau de sweat sock” are all ways to describe a certain aroma that develops due to standing water or bacteria growth in your air conditioner. Foul as it is, this air conditioning smell is usually not harmful.

WHAT TO DO: First, change your air filter if it has become wet or clogged. Next, call an HVAC pro to clean out your AC system, especially the evaporator coil and the drain. (Ideally, schedule professional maintenance every year.)

3. Musty Mildew

Another result of excess damp in your air conditioning is moisture that escapes via the airflow. It can get trapped in the ducts, leading to mould and mildew growth in the ductwork.

WHAT TO DO: As above, checking your AC filter for moisture or blockage is the best place to begin. If that doesn’t help, call an HVAC pro to clear out your condensate line and clean your ductwork.

4. Burning

A faint scent of burning occurs when you first turn on the HVAC system is usually nothing serious. A strong burnt or gunpowder odour can indicate an electrical fire hazard — a short circuit, motor overheating, or frayed wiring that is sparking.

WHAT TO DO: For a faint whiff, wait a couple of minutes to see whether it dissipates by itself. For a more pungent odour, switch off the system, evacuate your home, and call the fire department from outside. Once the situation has been stabilized, contact an HVAC company to repair or replace your air conditioner.

5. Exhaust Fumes

Your electrically powered AC should not smell of exhaust in everyday use, which usually comes only from burning fossil fuel such as gasoline. Exhaust fumes indicate there could be a leak in your refrigerant line or motor.

WHAT TO DO: Turn off the system and get emergency air conditioning repair.

6. Vehicle Coolant

Antifreeze, a significant ingredient of vehicle coolant, smells rather sweet, similar to Freon or R-22, a toxic residential AC refrigerant, which is in the process of being phased out by the Canadian government. A vehicle coolant-like odour inside your home warns you of a Freon leak — very dangerous since inhaled Freon is toxic.

WHAT TO DO: Stop running the air-con and open the windows wide to let in the fresh air. After that, call an HVAC refrigerant expert to find and fix the leak.

7. Cigarette Smoke

A scent of cigarettes results when someone frequently smokes indoors. The stale smoke tends to be absorbed by your HVAC air filter and the evaporator coil and then “recycled” throughout your home.

WHAT TO DO: Make a habit of changing or cleaning the filter every 30 days and having the system expertly cleaned at least once a year. And maybe think about quitting smoking…

8. Skunk

If it smells like a skunk, it probably IS a skunk. Skunks might spray your AC’s outdoor condenser unit if they are startled. The pungent odour will then be circulated through your ducts.

WHAT TO DO: Turn off the air conditioner to prevent spreading the odour even more. Open some windows to air out your home. Call your friendly neighbourhood HVAC tech to clean the ducts and the condenser.

9. Garbage

A noxious garbage-like odour usually means that a rodent, bird, or other critter has made its way into the ductwork and died there. Running the air conditioning is helping to spread the odour in your house.

WHAT TO DO: You’ll need to hire someone to remove the animal’s remains and clean your duct system. Until then, limit the spread by not using the air conditioner.

Keep Your AC Clean & Safe

If you have a question about air conditioner smells or other HVAC issues, don’t hesitate — call the Doctor. Dr HVAC’s team of trained technicians will clean, repair, or replace your air conditioning in the GTA.

GET FAST EXPERT AC SERVICE