Furnace cycles continuously

Old 11-23-20, 10:24 AM
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Furnace cycles continuously

I have a goodman gas furnace, model # GMS80804BNBA, thats not working. Truth be told I was adding a whole house humidifier (Aprilaire 700) and something went wrong. Installed the humidifier turned breaker back on turnd on switch on furnace. Blower starts running igniter heats up gas valve clicks then fuse pops (3a). I checked everything, went through 5 more fuses, after 5 fuse didn't blow anymore. Then I took off all the aprilaire wires and try again. As soon as the gas valve clicks the the igniter goes out and it starts the cycle over again. Furnace does not go into safety shutdown it will keep trying indefinitely. I checked as best I could all the components in the furnace and everything seems to be working. I found a control board at a parts supplier near me and after work will try to change that. I guess I'm here to see if there may be anything else I missed or if the control board probably fried because I did something wrong when adding the humidifier. Any advice would be greatly appreciated.
Old 11-23-20, 11:12 PM
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Welcome to the forums.

If your furnace was working ok before your wiring job..... you messed up.
Rarely does the board cause the fuse to blow. It's usually the low voltage wiring.

What version of the 700 is that ?
Some had a transformer in them. Connecting that to your furnace directly could have shorted the board.
What are you using for a humidistat ?

If you don't know which version you have..... connect the two wires coming out of the humidifier directly together. Does the unit start..... if yes you have the older self powered version with transformer.

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