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What Do Odd Smells From Your Furnace Mean?

Girl-pinching-her-noseTemperatures have dropped down to the point where you’ve probably turned on your home’s furnace at least once—and you can expect it to stay running for longer stretches as we move into another cold winter. 

When your furnace first turned on, you probably noticed a dusty burning smell coming from the vents. Strange odors coming from your furnace are often warning signs that something is wrong with it and will require calling our professionals to inspect the furnace and see if you need heating repair in Monument, CO

Below, we’ll look at what these odd smells could mean and when to act on them.

That initial burning odor

We’ll start with this, because you probably experienced it recently. The good news is that this smell is rarely a sign of a problem. In fact, it’s normal for the first time a gas furnace turns on after its mid-year hibernation. What you’re smelling is the burning off of the dust that has gathered over the heat exchanger during the off-season. The odor should subside in less than a day, possibly sooner. If the odor lingers, call our professionals. You may have a heater that needs cleaning.

A sulphuric “rotten egg” smell

Now we’re getting to odors that are warning of problems, potentially severe ones. This odor is one that comes from natural gas. Technically, it’s an additive put in natural gas called mercaptan that makes it easier for people to detect when there’s a gas leak. This odor is sending the warning signal that there’s a leak in the natural gas line that’s allowing gas to escape the furnace and enter the living space. This creates a huge fire hazard that even a small spark could ignite. Exit your home immediately and shut off the gas (if you have access to it from outside). Don’t call us for repairs: first call the gas company. You can work with us for repairs later when you know your home is safe.

An acrid, electrical burning smell

This burning odor is sharper than the smell of dust burning off the heat exchanger. There are several potential causes of this odor, none of which are good. The most common cause for a burning electrical smell is a motor that’s burning out or loose electrical wiring. (Keep in mind that gas furnaces still have important electrical components.) A dying motor will soon mean a non-operating furnace. An electrical problem could soon mean an electrical fire. Turn off the furnace at the furnace switch and call us right away. 

A “dirty sock” smell

This is an icky odor to have in your home, but it’s not an immediate health concern the way the previous two were. The smell comes from mold or mildew inside the HVAC system. If the mold and mildew start growing in the furnace, the heat will soon kill off the problem. The odor may also come from mold in the AC, which won’t go away as easily—even when you aren’t using the air conditioner. If the odor continues, arrange for us to inspect the HVAC system and find out the trouble. 

Robbins Heating & Air Conditioning serves Colorado Springs and the surrounding area. Call us for 24-hour emergency repairs for your home’s furnace or other heating system.

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