What smells?!

What smells?!

Common odours that could be coming from your HVAC unit

The heating, ventilation, and air conditioning (HVAC) unit in your home is one of the most-used appliances. When it isn’t working well, things can get a little inconvenient and uncomfortable in your home. Fortunately, it’s pretty good about letting you know when it’s time for servicing.

When your HVAC unit emits unpleasant odours, it’s telling you that there is a problem. Some odors are harmless and some are not.

To help you solve the source of the smell in your home, here are some common odors and possible sources:

Bacteria growth

When bacteria grows on the coils of your heat pump, the nasty smell is commonly described as dirty socks. Most often, the smell is remedied with a quick tune-up performed by an HVAC professional.

Electrical issues

If your unit smells like it might be overheating, there’s a good chance that it is.

Turn your unit off before attempting to diagnose the problem. Start with the air filter to see if it’s dirty and restricting air flow. This can overheat the electric resistance heaters.

If the issue isn’t the air filter, an electrical problem is likely the culprit. Make sure the electricity is turned off at the master switch and call in a professional HVAC technician.

Don’t attempt to fix this yourself! Doing so could result in serious injury, or death.

Gas leak

Natural gas leaks are always a concern, even with a properly maintained unit. If a strong smell of rotten eggs is present in your home, it’s a sign that you should immediately turn off the gas and call in a professional to inspect your system. Natural gas is odorless, but gas companies add a harmless chemical to the gas to make leaks recognizable.

Once the gas is turned off, it’s important to avoid using electronics or open flames near the area of concern. This will help avoid fire or an explosion.

Poor ventilation

A common source of unwanted smells can result from poor ventilation in your home. Today’s energy efficient windows, doors, and insulation leave little room for air to escape your home. While that’s excellent news for your wallet, proper air ventilation and circulation is prevented.

This lack of fresh air for circulation in your HVAC system often leads to stale air, but can also become the source of more unpleasant odors. If this is an issue, let fresh air into your house as much as possible. Warmer, sunny spring weather provides a great time for this.

If the smell persists past a good dose of fresh air, it’s time to call in a professional.

Refrigerant leak

Whether you have an air source heat pump, a ductless heat pump, or a traditional air conditioner, your system needs refrigerant to provide your home with cooling power.

Refrigerant can leak, causing a strong acetone odor in your home. If you smell acetone and it’s not from the use of nail polish remover or solvents, there’s a good chance that your unit has a leak.

Leaking refrigerant ruins the effectiveness and efficiency of your HVAC unit, and poses a health and fire hazard if exposed to an open flame. A skilled professional can easily locate the leak, repair the damage, and replenish the refrigerant.

Unwanted guests

A strong urine smell emitting from your HVAC unit is a sign that some portion of it has unwanted guests. Mice urinate and defecate in their homes frequently. Unfortunately, the unpleasant smell will come through your vents when the furnace or air conditioner is running.

To rid yourself of this gross aroma, you’re going to have to get rid of your unwanted guests. Calling in a professional is often the quickest way to get rodent free.

Once your guests have been removed, an HVAC professional—like us—can offer suggestions on how to improve the air quality of your home.


If you’re heating system has been off for a long period of time, you could start to smell something like burning gas when you first turn it on. If the smell doesn’t persist, there is nothing to be alarmed about. Dust has gathered on the heat exchanger while not in use, and is simply burning off. Typically, the smell shouldn’t last long and there’s no need to worry about it again.

Should the smell continue to be an issue, call in a professional to access the situation.


Nothing’s worse than having a gross or strange smell in your home. Undesirable smells could be as simple as changing a dirty air filter, or they could present a serious health hazard that requires immediate attention. Either way, you’re going to want to get the source of the smell!

We can help identify the unwanted smell and fix the problem. Call us at 250.465.2490

We are always happy to help you keep your home smelling great and your family safe.

Routine maintenance catches problems with your unit before they become serious and costly.




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