Skip navigation

Serving the Greater New Braunfels, TX Area

Serving the Greater New Braunfels, TX Area


Why You’re Getting Weird Odors From Your Air Conditioner


The air from your air conditioner should smell like … well, like the rest of the air in your house. If you have a clean home, the air from the AC shouldn’t have any noticeable odor. After all, it’s the same air from the rest of the house, but circulated through the AC to have heat removed from it.

But what if the air coming from the AC doesn’t smell right? You’re detecting strange odors from it that it’s never given off before. If you think this is a bad sign, an indication you need air conditioning repair in Seguin, TX from our expert techs, you’re probably correct. Below, we’ll take a look at the different AC odors you may notice and what they can mean.

The dirty sock smell

This is a common odor from an air conditioner. So common that it has its own title: dirty sock syndrome. It’s a descriptive name and we don’t think we need to describe it much more to you. What this smell means is mold and mildew inside the air conditioner. This can start for several reasons, such as a clogged condensate drain that isn’t removing condensate water from the AC fast enough. The higher moisture is an invitation to mold and mildew to start growing.

Mold often develops along the evaporator coil, and that means all the air moving past the coil and into the house will pick up this moldy odor. Professionals will need to fix whatever is caused mold to develop, because not only does this make your house smell terrible, it will also lower AC efficiency. 

The gunpowder smell

An acrid odor like this is telling you there’s an electrical problem in the air conditioner or a burnt-out motor. The electric control may have shorted out, or a motor overheated to the point its wires fused to the housing. The AC probably won’t run much longer with these problems (it will likely trip a circuit breaker), so call for repairs ASAP.

The rotten egg smell

This is an odor people often associate with sulfur and gas leaks … and that may be what’s going on. “But wait, the AC doesn’t run on natural gas!” you say. That’s true. But the air conditioner and the gas furnace are often in the same HVAC cabinet and share use of the blower fan.

If gas is starting to leak from the furnace, it can enter the air sent through the air conditioner. We recommend you shut off the gas to the house and call for help from the gas company first. You can later call us for AC or furnace repairs.

The car exhaust smell

This is the same problem as the rotten egg smell: combustion fumes are getting into the air conditioner. Follow the same procedure.

The dead animal smell

Sorry to tell you this, but this odor is often exactly what it smells like: there’s a dead rodent somewhere in the ventilation system. Fixing this doesn’t involve the air conditioning; it involves getting the ducts cleaned. You won’t want this odor hanging around your house for long.

At Thayer Air Conditioning, your comfort is our #1 priority! Call us for emergency service when you’ve got an AC problem—we’re already on our way! 

Comments are closed.