# Natural Gas Forced Air Furnace Blowing Cold



## DXHum (1 mo ago)

Hello 

Approximately 2 weeks ago, I felt a draft while sitting in my living room. When I investigated, I came to find that the air blowing from the vent was cold. So I went down to the furnace and is sounded like it was running normally, except that the burners were out. It was as if the flame sensor didn't detect the burner flame was out and the blower motor just kept running.

I turned the power off via the switch located on the side of the furnace and waited a minute or two. Then I powered it back up, and it ran fine for about 10 minutes. Then the burners went out but the blower motor continued to run.

The first thing I thought of was air flow, or a lack there of. So I pulled my air filter (which was due to be changed) and replaced it with a new one. I also pulled the flame sensor and cleaned it using a small wire brush and rubbing alcohol.

I put everything back together and it appeared to work well again... until this morning, when I again noticed the air was blowing cold. Again, I powered the furnace off from the switch on the side of the unit, waited a minute and then powered it up again. Now its blowing warm.

I'm not sure what's going on here.

Any guidance is appreciated.

Thank you!
Dx


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