Does Your AC Smell Strange? What those Odors Mean and how to Fix Them
If you smell mold, something burning, sewage, gunpowder or something rotten, and it seems to be coming from your air conditioning system, you might have a problem.
An AC smell could indicate
- dirty filters,
- mold growth,
- electrical problems and
- refrigerant leaks.
Some of these require immediate attention.
Musty/moldy
A musty or moldy smell can indicate mold or mildew growth from moisture buildup in the drain pan, coils or ductwork.
The indoor coil and its drain pan can be a favorite hangout for mold and bacteria. Growth of these organisms can affect efficiency and reduce airflow. They can even become airborne.
Mitigate this problem by cleaning or replacing the air filter, cleaning the drain pan and coils, and ensuring proper drainage from your HVAC system.
If the problem is recurring, you may want to consider putting UV germicidal lights inside the HVAC system prevent mold and allergen buildup on the coils.
UV lamps are designed to kill the mold and bacteria to help keep your system efficient and clean air flowing.
Dust, dirt and debris build-up on the air filter can also lead to a musty smell. You should clean or replace the air filter every 1-3 months.
Burning
A burning smell is usually caused by an electrical malfunction, overheating or a burning component.
You don’t want to mess around if something is burning. To be safe, turn off the AC immediately and call any of the highly-recommended local HVAC companies.
Exhaust fumes
A smell like the exhaust of a car can mean a refrigerant leak, which is potentially hazardous to human and animal health, along with the environment.
As with a burning smell, your best course of action is to turn off the air conditioner and call the company that regularly services your HVAC equipment.
Rotten egg or sulfur
If you smell rotten eggs or sulfur, you might have a gas leak, particularly if your home comfort system runs on natural gas.
The smell comes from mercaptan, which is added to natural gas to make gas leaks detectable.
In this situation, turn off the main gas supply, evacuate the house, and call your gas company immediately. It may seem like overkill, but it is better to be safe than sorry, right?
Until your gas company representative gives the all-clear, do not use gas or electrical appliances or light any flames.
Dead animal
If you smell that sickly, rotting smell of an animal decaying, you may have rodents or insects trapped in your ductwork.
You will need to locate and remove the source of the smell, perhaps with the help of an animal control company or your trusted HVAC provider.
How to find what is causing the smell:
- Follow the odor trail to the most concentrated area.
- Inspect behind appliances, in wall voids or under cabinets.
- Rodent urine and fur can be detected by a blacklight.
- Check your ventilation system; the odor might be circulating that way.
Once the animal has been removed, open your windows and doors to let in fresh air and clear the odor.
Sewage
Cracks in the sewage line near the HVAC system or condensation buildup in the split unit may be the cause. Inspect the sewage line and address any leaks or condensation issues. You may need a plumber to help.
Gunpowder
This distinctive smell can be caused by a burning fan motor or other electrical component. When you detect this odor, turn off the AC immediately and call a professional.
If in doubt, call a pro
If you notice any unusual smells, the best HVAC contractors all recommend addressing them promptly to avoid potential health hazards or costly repairs.
Jansen Heating & Cooling will be glad to come out and help with any heating or cooling issues, including determining the cause of these odd smells. Contact us any time.