9 Yucky Air Conditioner Smells And How To Fix Them!

Man plugging his nose for a smelly air conditioner.

Ew! What is that terrible smell?

You’ve already searched the basement, bedrooms, bathroom and kitchen for the mysterious source. But no luck!

In fact, you’ve practically gone in circles a dozen times hunting for the culprit. However, the smell doesn’t seem contained to one location. It actually seems to be coming from… everywhere.

Don’t give up!

Not being able to find the culprit is your first clue!

Have you considered that the odour could be coming from your air conditioner?

Your A/C is not very discreet. And it continues to circulate air, no matter what it smells like! After all, that’s its job.

But it’s hard to breathe normally when indoor air smells like car exhaust or rotten eggs!

Let’s learn how to identify and get rid of these unwanted smells!

Ready to catch that stinking culprit? Get your sniffer on!

What do you smell?

Burnt Dust

You may have noticed this smell when you first turned your air conditioner on in the spring. And that’s normal! The smell of burning dust is usually due to your A/C being off for so long in the winter. Once you turn it back on, it will essentially burn off the dust and emit that burning smell.

But after about 20 minutes, this smell should be gone.

If it’s not, there could be an electrical or mechanical problem within your A/C.

A burning smell in your A/C could point to a problem in your:

  • A/C Circuit board
  • Power Wires
  • Compressor
  • Fan motor

If this is the case, turn off your A/C unit immediately and exit your home. The fumes you’re smelling could be dangerous!

Here’s What You Should Do:


The smell of gunpowder is another telltale sign of electrical fire hazards.

If you’re smelling gunpowder, your fan motor or circuit board has probably fried.

And because both of these contain varying metals and chemicals, they’re considered hazardous to your health!

The Solution:

  • Schedule A/C Repair

Rotten Eggs

The smell of rotten eggs is a sure sign of a gas leak. So if you start to smell it – get out fast!

Natural gas is odourless, but utility providers add this aroma to help keep people safe. If left unchecked, a gas leak can cause fires, explosions and severely reduced oxygen levels.

The smell of rotten eggs instantly alerts occupants of the problem, giving them enough time to evacuate and call for help.

Here’s What You Should Do:

  • Turn off your gas supply.
  • Evacuate as quickly as possible.
  • Call the fire department.

Car Exhaust

Other fluids within your A/C can leak too!

For example, if your air conditioner has a refrigerant line leak, you could smell exhaust fumes – like car exhaust!

While not as deadly as a gas leak, refrigerant is also a hazardous chemical. And it’s not only bad for you but bad for the environment too!

Here’s What You Should Do:

  • Open all your windows and doors to ventilate your home.
  • Call for Emergency HVAC Repair.


Dampness in your home is never a good sign. And if you follow along with our sister company, Shiptons’ CleanAir Solutions, you know all the effects damp air has on your home and health.

Damp air in your home means you have high humidity. And high humidity can cause mould, mildew, water damage and more!

So what happens when you smell mould in your home? Check if the odour is coming from your ductwork!

Excess moisture from your air conditioner can get trapped in your ductwork and cause mould and mildew growth.

Here’s What You Should Do:


There are many potential culprits for the chemical aromas in your home. Some of those originate in your air conditioner. But they may come from your ductwork or even an intake vent.

Chemical Sources:

1. Open chemical containers near the intake vent or ductwork.

Have you stored a paint can or other chemical-containing liquid near a vent? This could actually be the source of chemical odours in your home!

If left open or improperly sealed, these containers can begin leaking. And if they’re close enough to your vents, it’s not difficult for them to enter your home’s airflow!

2. The air conditioner unit.

If your air conditioner malfunctions, it can actually start emitting any number of the chemicals used to manufacture it.

One example of a harmful chemical that your A/C unit could release is formaldehyde. A member of the VOC (volatile organic compound) family and hazardous to your health.

3. Certain air filters.

Air filters trap harmful pollutants and ensure you have clean, breathable air in your home. But not all filters are of equal quality.

For example, electrostatic-type air filters can actually produce ozone!

  • Ductwork glue.

Did you just get ductwork installed? The chemical you’re smelling may be the glue used in that installation.

While you can’t remove the smell instantly, it will eventually fade as the glue dries.

Here’s What You Should Do:

  • Properly seal and store all chemical-containing products.
  • Schedule A/C Repair.

Cigarette Smoke

If you smell cigarette smoke in your home, that’s probably exactly what it is. It’s hard to get that scent out of your home once it’s had a chance to circulate your air and stick to your furniture.

That’s why when people try to sell their furniture online, you’ll notice this comment, “from a smoke-free home”!

Here’s What You Should Do:

  • Change your air filter every 30 days.


Unless you’ve forgotten to take the trash out for a couple of weeks, that garbage smell could mean there’s an unwelcome guest in your ductwork.

Occasionally, rodents or birds can get trapped inside your ductwork. And if you don’t realize it’s there, chances are, it’ll die there too.

The result?

The odour from the animal then spreads throughout your entire home as your ductwork carries it from room to room.

Here’s What You Should Do:

  • Avoid using your air conditioner until you can schedule a duct cleaning appointment.


Smell a skunk? You’ve been sprayed! Or rather, your outdoor A/C condenser has.

Thankfully, if it’s just your condenser that got hit, getting the smell out is a quick fix!

Here’s What You Should Do:

  • Try not to use the air conditioner until your HVAC technician has cleaned the condenser and the ductwork.

For Expert A/C Service, Call Your Shipton’s Cooling Technician!

Which air conditioner smell is affecting your home? Let’s get your air conditioner back in order – fast!

Give our HVAC service technicians a call for a quick clean, repair or replacement! We’ll ensure your air conditioner is stench-free and in top condition.

Reach us at (289) 203-4616 or contact us online!

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