Why Is My Furnace Blowing Cool Air?

It is a problem that no one wants to encounter. You are in your home, your furnace is running, but you’re still not feeling warm and cozy. You walk over to an air vent where you discover that not only is the home not warm and cozy, but the furnace is actually blowing out cool air! Not ice cold, of course, but cool. And that is a big problem.

It goes without saying that this is the type of problem that homeowners don’t usually wait on finding a way to fix. When you need to heat your house, you’re very unlikely to ignore a furnace blowing cool air. But before you do contact us about your furnace in Tallahassee, FL, you should check at least one thing. More on that below, so read on and learn more about why furnaces might blow cool air.

First Things First, Check the Thermostat!

We love our clients, but we don’t want to come out to your house if you don’t really need us. That is why you should always check your thermostat if your furnace is sending out cool air. Yes, it sounds obvious. Yes, homeowners do miss this from time to time. What’s the problem?

It’s possible that your thermostat got switched over to a “fan-only” mode. If this is the case, then you will feel air coming from the vents. However, your furnace won’t actually be heating that air. You definitely don’t need a professional HVAC technician to change the setting at the thermostat, so rule out this simple fix before making the call.

Limit Switch Malfunctions

The fan in your furnace starts up when air is sufficiently warmed. It blows that warm air through the house, and continues to do so for a bit even after the burners shut down. Once the heat is dispersed, though, the fan shuts down. At least, it does when the limit switch is operating properly.

If your fan limit switch malfunctions, then it can actually keep the fan running even when no heat is being generated.  This will result in the same problem above, but it’s not something that you can just fix at the thermostat. Fortunately, a professional heating technician can replace a fan limit switch in short order.

Air Duct Leaks

There is a lot to be said for forced air heating systems like furnaces. The fact that they heat air directly and then circulate that heated air through a system of ductwork means that they can heat up homes quickly. However, there is a potential drawback of these systems: air ducts can develop leaks.

If your ducts are leaky, then you may notice uneven heating in your house. Heat may leak out of a section of ductwork, and the air coming from the affected register will feel cooler as a result. Professional duct sealing is the only way to deal with this problem. You can’t fix this on your own.

Schedule your furnace services with Parker Services Inc. Comfort’s just a call away.

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