Your HVAC system runs most of the time, sometimes cooling, sometimes heating, and always circulating air. Occasionally, you may notice there are odors that come in with the air flow. They can be unpleasant, annoying, or barely noticeable. But whatever the smell, it’s usually worth finding out why it’s there.
Problem: Musty/Moldy Odor
A smell like mold or mildew is a common one, but if you’ve been noticing a musty or moldy odor from your vents, it can be difficult to pin down the source. It’s important to do this, however, because while mold and mildew aren’t serious problems for your equipment, they can lead to respiratory health issues due to poor air quality. There are a few reasons you might be experiencing this.
Solution: You need to have an HVAC technician find where the mold build-up is, and have it cleaned up properly.
Solution: Talk to a HVAC provider to see if your unit is too large and go over your options for a high efficiency replacement.
Solution: The easy remedy is a routine maintenance call and/or tune-up.
Problem: Burning Odor
Sometimes when you turn on your furnace for the first time of the season you’ll get a slight odor like a hot iron or something scorched. As long as this doesn’t linger too long, you don’t have to worry. Dust gathers on the heat exchanger of the furnace when it’s not being used and then burns off when the furnace gets turned on for the first time in a while.
Solution: Turn off your furnace right away before doing anything. With the power off you can check your air filters, and if they’re fine and you suspect a problem with the wiring, contact an HVAC professional right away. You should not attempt to repair an electrical problem yourself.
Problem: Acetone Odor
Solution: Contact an HVAC technician to inspect your system, find the leak, repair it, and replenish the refrigerant.
Problem: Urine Odor
Solution: Find where the mice are living. In cooler temperatures it may be around the air handler (it’s warm there) and then you need to clear them out. After that you’ll probably need to clean your ducts and install some kind of air filtration system.
Problem: Rotten Egg Odor
Solution: Turn off your gas immediately, open windows, and call an HVAC professional to come out and inspect your equipment. In the meantime, don’t use any electronics or light any candles near the area – sparks and open flames could cause an explosion. In fact, it’s a good idea to leave the area until you have the problem addressed.
Problem: Stale Odor
Solution: Open the windows every now and again and let the fresh air outside circulate through your house.
Keeping the air in your vents smelling clean and fresh is usually just a matter of keeping your air filters changed regularly. When an odor results from something else, you should have your HVAC inspected by a trusted local company like Air Specialist. An annual maintenance contract often catches small problems before they become big ones.