Why Is My Heater Blowing Cold Air?

man checking a heater duct

It’s cold outside, which means it’s time to bundle up under some blankets in a nice heated home. That sounds nice, but your heater is blowing cold air—no warm and cozy for you. There are several components in your heating system including, but not limited to your ductwork, blower, and heat exchanger. Before the warm air gets from your heater to you, something can go wrong in any one of those parts. Here’s a list of four issues that can cause your heater to blow cold air.

1. Your thermostat is set wrong 

This seems a bit obvious, but many times it’s the simple things that get you. If you notice that your heater is blowing cold air, make sure it’s set right. Your fan should be set to “auto” rather than “on” because in that setting it will blow air even when the heater isn’t heating. Also, check that your thermostat is set higher than the temperature in the room. If that doesn’t work, it could be that…

2. Your heater isn’t getting any fuel

Heaters operate on gas, electricity, or oil. Each type has its associated problems. An oil furnace might need to have its filter replaced. A gas furnace might have valve issues. Finally, an electric furnace may have tripped a few switches. Without the proper fuel operation, your heater will not be heating air anytime soon.

3. Your ductwork is compromised

Before the warm air from your heater gets to you in your bedroom, it has to travel through a fair amount of ductwork. The problem is that ductwork is usually in the attic, and it isn’t covered by insulation. If there are any holes in your ductwork, the warm air will simply leak out. In this case, your heater is functioning, but you won’t feel a thing.

4. Your system has reduced air flow

The blower takes cold air from your home and blows it across the heat exchanger. The heat from heat exchanger then transfers to the air. If there is reduced air flow in your system, the heat exchanger can overheat. It will just retain all the heat because there is no air to transfer it to. This will trigger a safety switch, and your heater will proceed to blow nothing but cold air.

If you don’t know what’s causing your heater to blow cold air or don’t know how to fix it, call the AC repair experts at Cypress Creek Air Conditioning & Heat. You can reach us by dialing 281-817-6454 or by filling out an online form.