Goodman Open Limit Switch Problem
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Goodman Open Limit Switch Problem
Hi Folks-- I have Goodman gas furnace (model GMT090 4B). I have no heat-- only cold air blowing out of my registers. The LED indicator flashes a code indicating "Open Limit Switch" and says is need to "check main limit open, aux limit open." We're @#$% freezing and I have three little kids. Please help!
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Heating Repair
Make sure you have a clean filter in the system and that your fan is running the limit is located behind the gas valve and it will have two wires on it. If it is open with the furnace cool the switch is bad and will have to be replaced. If there is an auxilairy limit on that unit it would be on the blower housing.
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Thanks-- Follow Up
Make sure you have a clean filter in the system and that your fan is running the limit is located behind the gas valve and it will have two wires on it. If it is open with the furnace cool the switch is bad and will have to be replaced. If there is an auxilairy limit on that unit it would be on the blower housing.
I think I located the switch-- little black circle with a red tab sticking up. Does that red tab indicate a blown limit? Can I do anything to get through the night? Thanks...
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Heating Help
If that reset button is tripped just push it in and it should start but it tripped for a reason and the reason will probably be apparent when it restarts. A limit switch is not usually manual reset. That would be a rollout switch, if you reset the switch and the furnace starts and the flame stays in the chambers where it belongs the switch may be going bad but most likely you have a bad heat exchanger I would call for service for safety reasons.