Hello all,
Having an issue with my Goodman furnace (GMS90703BXA), looking for some advice. Came home from vacation to a Open High Limit error code. A pretty dirty filter may have caused this (oops). Changed filter and reset power. It worked for the night, but tripped the OHL code in the morning. Now it won't function normally at all, even after resetting power.
After turning the power back on, light is steady on. When I kick the heat on, both the main blower and the ID blowers turn on (usually main blower doesn't turn on until after the flame ignites). ID blower will run for a few seconds, then turns off. Never reaches the ignite step in the sequence. Light flashes 4 times (Open High Limit). Main blowers stays on the whole time.
Both pressure switches seem to be working, but I have noticed with the pressure switch on the right (ID blower switch) I get continuity between the two wires connecting it. Is this normal?
I get continuity on the primary limit switch as well.
Any help on my next steps in diagnosing is very appreciated.
Thank you!
Pics (https://imgur.com/a/wfe2Mii)
Some models have one or more auxiliary limit switch near the blower. And some models used a manual reset limit, so I would make sure those switches are closed. They sell a kit to replace it with an automatic reset switch.
Quote from: Admin on November 02, 2023, 07:53:37 PMSome models have one or more auxiliary limit switch near the blower. And some models used a manual reset limit, so I would make sure those switches are closed. They sell a kit to replace it with an automatic reset switch.
Thank you. I did find an auxiliary limit on the circuit, but it tests fine. Circuit even tests <1ohm pin to pin on the molex connector.
Then likely the control board is faulty.
https://www.amazon.ca/Upgraded-Replacement-Goodman-Furnace-PCBBF112S/dp/B00EFAXQJS/ref=asc_df_B00EFAXQJS/?tag=googleshopc0c-20&linkCode=df0&hvadid=459849899264&hvpos=&hvnetw=g&hvrand=11413664315790029917&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9104499&hvtargid=pla-581883481107&psc=1&mcid=95a825bdd7db3ea5b311a2478153a855