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Furnace Odors and What They Mean


When you first turned on the heating system in your San Antonio, Texas home, you probably experienced unpleasant furnace odors. This is not uncommon as over the previous months, dust and lack of use created conditions that contributed to these odors. If those smells have lasted, however, you should contact your HVAC technician as soon as possible.

Musty Odors

Does your furnace have a musty odor? This could signal mold growth. The most likely source could be a damp, dirty furnace filter. If you have a humidifier installed, check its filter.

Since you don’t want mold and mildew circulating through your home, check both the humidifier and furnace filters. Change the filters if necessary, and be sure to follow instructions regarding cleaning or replacing your filters.

Burning Dust Smell

The smell of burning dust is one of the most common odors associated with furnace operations. This odor is typical when you first turn on the furnace — but shouldn’t last for long.

Dust accumulates in the ductwork throughout the year and burns off when the furnace comes on. If you can’t get rid of the burning dust smell from your home, your system may need duct cleaning or other services.

Electrical-Burning Odor

If the burning smell that is bothering you is sharper, almost like a heated electrical unit, check your floor ducts to see if any item(s) fell through the vents. If you cannot track down the source promptly, contact one of our HVAC service professionals to help you find the cause. You may have a cracked heat exchanger or other more serious problem that could lead to a fire.

One of the most effective ways to prevent this and other problems, is to make sure that you keep up with regular maintenance. To ensure your system is ready for summer, be sure to schedule preventive maintenance this spring.

For more help diagnosing and resolving issues with furnace odors, contact Air Experts today at (210)-653-3350. We can help you keep your heating and cooling systems in good working condition to tackle any kind of weather.