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Where is the red light? On the thermostat or on the control board in the furnace?
The red light is on the control board inside the furnace, it shows through a clear little bubble in the outside panel. I didn't notice it last night when I was in the garage, but did tonight.
That is the 'status' light... It gives a fault code if there is a failure in the furnace, but it also gives the status. Generally the slow blink is normal and the fast blink would indicate a call for heat. Sounds like it's operating normally if you're getting heat. If it had a problem it would be flashing a code in sequence, like one, two, three or four slow flashes... A pause then repeat the code.
OK, so it does blink faster when the heat first comes on. When the heat goes off, it blinks slower. So it will just blink that slow blink when it's just hanging out and not working?
Correct... That would be 'normal operation' mode... Standing by waiting for a call for heat. Basically the ignition board 'self checks' and if the electronic internals are ok.. That's what it will do...
Sometime if you have the cover off of the furnace, look for a wiring diagram.. There is usually a legend on there, that will tell what the different flash codes are, including the slow and fast blink. That's generally on the inside of the lower cover
Thank you so much. I was freaking out thinking that it might be ready to explode or something. I tried looking at that diagram inside the cover, but it was really hard to read (I'm old!) and I couldn't find blinking lights. Thanks for your help!
Well they usually print those things so they're darn hard to read that's for sure... I"ve struggled with a few!
You're welcome.. Anything else I can do for you?
Yep! So now I can sleep without being worried, Thank you!
No problem. Thank you! Stay warm...