Mid trip furnace issues, how to troubleshoot?

Fasttimes · 02-17-2021, 03:20 AM

Mid trip and needed the furnace last night. It came on briefly, ran for about 5 min and shut off. I assumed because thermostat turned it off because temperature reached. I shut thermostat to off going to bed.

Woke and turned heat on and furnace will not come on. Not blowing any air. I can hear a click at the AC control board but furnace does not kick in.

Any ideas? How do I troubleshoot this? Clueless when it comes to furnaces.

backtrack15 · 02-17-2021, 08:14 AM

Since it worked before: Did you check for a blown fuse?

Fasttimes · 02-17-2021, 08:44 AM

I don’t see an obvious “generator” fuse in my fuse box. “Heat pump” maybe, not sure if same thing.

Opened up panel on furnace and see blinking red light in circuit board and a humming noise. If I turn off heat on thermostat humming stops. Reviewing online about blinking light I tried cutting power for 30 seconds to see if it would reset but it did not.

Also reading could be low propane pressure setting off warning. Guess it could be, but I think thank is 1/3 full. May go fill it more and see if it makes a difference.

backtrack15 · 02-17-2021, 09:20 AM

I’d test all the fuses 10AMP and higher in the fuse panel to see if any have blown. You might also confirm your batteries are charged up. Those are the easy things to check. Hopefully somebody else will chime in soon with additional experience.

Edit: maybe this video would be helpful (title sounds promising)

https://m.youtube.com/watch?v=yjTbZEs5VwI

Fasttimes · 02-17-2021, 12:03 PM

Fuses look ok. Not sure what’s going on. I found a wire somewhat loose, reattached. The started moving wires around and all a sudden the motor kicked on. Then. Would light and blow hot for a sec then the igniter would kick off the flame and blower still ran. It kept doing that for a while till I turned it off. Then when I tried to test again I was unsuccessful in getting blower motor running again.

Fasttimes · 02-18-2021, 09:49 AM

Was able to get a mobile mechanic to come by today. Turn out there was evidence of water under the control board. Some rust residue on back. We cleaned up the control board and coated in dialectric grease. Resealed the housing. Seems to be working fine now. If I encounter any more issues I will swap the control board out for a "Dinosaur" board off of Amazon.

golden13 · 02-21-2021, 05:06 PM

Quote:

Originally Posted by Fasttimes

I don’t see an obvious “generator” fuse in my fuse box. “Heat pump” maybe, not sure if same thing.

Opened up panel on furnace and see blinking red light in circuit board and a humming noise. If I turn off heat on thermostat humming stops. Reviewing online about blinking light I tried cutting power for 30 seconds to see if it would reset but it did not.

Also reading could be low propane pressure setting off warning. Guess it could be, but I think thank is 1/3 full. May go fill it more and see if it makes a difference.

I just wen through something similar. In my case, water had gotten into the furnace compartment and shorted it out. They are not terribly expensive, and it's pretty obvious how to change it. The wires are all color-coded. Just switch one wire at a time, and save yourself a service charge! Be extremely cautious if you open up the throat of the gas valve. Even a tiny scratch in there from a screwdriver blade can cause it to malfunction permanently.

This can cause the problem as readily as a buggy thermostat.

Morich · 02-21-2021, 05:44 PM

This being winter, it may be a good time to mention a hazard that can get really weird. Things are designed avoid rain but when there is snow and wind blowing it around, it can go up and into things that rain will not.
after a blowing snow, it is often a good idea to check the places like furnace and water heater where we have boards that might get wet from the snow. The snow may not hurt anything if it is just setting there but when it melts and we try to use things, it can get ugly!

Fasttimes · 02-22-2021, 09:54 AM

Quote:

Originally Posted by golden13

I just wen through something similar. In my case, water had gotten into the furnace compartment and shorted it out. They are not terribly expensive, and it's pretty obvious how to change it. The wires are all color-coded. Just switch one wire at a time, and save yourself a service charge! Be extremely cautious if you open up the throat of the gas valve. Even a tiny scratch in there from a screwdriver blade can cause it to malfunction permanently.

This can cause the problem as readily as a buggy thermostat.

Yeah, looks like the board is messed up. That same night after the repair it didn't want to ignite the flame. I ended up playing around with the lines and board and got it to, but pretty sure it's hosed. I got one from Dinosaur that just arrived today that hopefully sorts it out. Looks pretty simple to swap out.