Furnace blowing cold air

Furnace blowing cold air..serviced yearly ...filter changed each month...it’s about 14 years old

Any input?

Thank you!

gas? is the pilot light lit? is the gas valve switch is in the “on” position?


Did you run out of oil?

It’s oil...pilot light on and 1/2 tank full of oil

Mine did the same thing...if it is gas then the pilot is probably out.

March 13th

I had a similar issue - Is the top of the furnace (waist high) hot (unusually warm? ... compared to the other furnace {assuming you have 2 units...for top&ground floors}

There's a switch that prevents it from burning up...so when hot, it will prevent the furnace heat the air up.

If so, (luckily & depending on your "yearly service" firm), they need to change the switch (as it sometimes/over time burns out or becomes defective) that needs to be replaced at a small fee.

On the other hand, if the blue-fume (you can see through the glass view) is orange and/or not directly flowing/blowing into the 'firing'? tube, then more work needs to be fixed or replaced (which costs much more).

*Just to do a little DIY try to fix it or verify that's the problem [or even pilot light issue skippy mentioned] before calling your service firm, I'd shut down the units, unplug them, give them some time to completely cool off (about an hour? or less?), then replug it, and see if it works/restarts the unit (switch or pilot) to work to norm again*

Hope that works

ftcfda@aol.com ftcfda@aol.com
March 13th


you can check the flame sensor

ftcfda is also correct in that it may be over heated.. try the reset first and then check flame sensor

The OP should NOT try to fix the problem themself!!! They are saying it's an oil fired furnace but the pilot lite is on??? Come on they obviously don't know what they have and could do harm to themself and or the unit!! Call an expert please! !!

March 13th

Well for one not everyone has money and 2 everything that was suggested was a visual inspection or turn it off.

Thank you very much for everyone’s help!

This is such a helpful and knowledgeable group

I had my heating person come out and he replaced the “computer “ for lack of better explanation and it’s working great

I’m glad

FYI, The control board will usually have the ability to blink a code at you telling you what is wrong. List of codes should be available in the manual or you can search make/model and download one.

MeisterNJ MeisterNJ
March 14th

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