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View Full Version : Need heat.. help


craigslist4059
Jan 23, 2011, 08:27 AM
I have a older johnson magic chief furance. Was installed in the house around 1980s

The other day the furance died we noticed heat was off. Went down and the blower motor actually went out on it. Replaced bower motor and belt. Fan kicks on burners ignitite. And then burners turned off. Blower kept running.

Ended up also have a faulty / older limit switch so we replaced the limit switch also.

Starting with a cold furance the limit switch moves , calls for heat and heats the exchanger, then kicks on the blower but then doest hold it position just continues to move and hits the heat limit. Then doest allow the blower to shut off. You can go and turn the thermostate down below what its reading by 20 degrees and blower will not shut off just keeps running.

We matched the blowers, limit control exactly. Also replaced thermocouple , belt , filter all why we were in there. There is really only a few electrical things left like the thermostate , a transformer for the gas valve.