Why Is My Furnace Blowing Cold Air?

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Why Is My Heater Blowing Cold Air?

If it’s winter in the Denver area and your furnace is blowing cold air you have a problem that needs to be solved and quick.

The temperature outside dips lower and lower. So you go to turn on your furnace, looking forward to that warm air. Instead, you’re greeted by the furnace deciding to blow cold air.

Below are a few reasons your furnace is blowing cold air.

Heater Needs To Warm Up

If you’ve just bumped up the temperature or if you’ve just turned your furnace on for the first time.

It may just be as simple as your heater needs some time to warm up. Allow your system to run for 5-10 minutes to see if the air warms.

Check Your Thermostat 

Thermostats make our lives so much easier. They’re also the first place you should look if your furnace isn’t working properly.

For example, if your thermostat is set on the” on” position instead of “auto,” the furnace will continually run, even if it isn’t on the heat cycle.

In that case, cool air will be running through the system, which means a simple thermostat adjustment.

Next, if your thermostat runs on batteries, check those to ensure they are not weak or dead. If you have a programmable thermostat, ensure that your thermostat is programmed correctly.

Check The Pilot Light

If the gas supply is interrupted for any reason, the gas furnace pilot light will go out, which could cause your heater to be blowing cold air.

You can fix this problem by following the instructions to relight your furnace’s pilot light.

If your pilot light refuses to remain lit, this indicates an issue that will need to be fixed by a professional.

Condensate Line is Clogged

High-efficiency furnaces have condensate lines that move water away from the furnace.

A clog in the condensate line will prevent your furnace from igniting. No ignition means only cold air coming through your vents.

There could also be an issue with your condensate drain lines, but an HVAC technician will be able to tell you exactly what the problem is.

These issues are the most common ones that arise and result in your heating system’s inability to warm the air and you receiving the cold blast from your air vents instead of the heated air you want.

If you experience the problem of the furnace blowing cold air, this list may help you discover the issue and make the fix.

Remember, if you can’t get your furnace back up and running we can help.

Denver Furnace Repair from First String Heating

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