Furnace won't turn off at desired temp

Old 12-02-10, 11:22 AM
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Post Furnace won't turn off at desired temp

Natural gas furnace , heat cycle continues forever. Std 4-wire setup. Settings: heat/ auto fan. Gas shuts off at desired temp, but cycles back on again (temp rises in home until heat is turned off). Replaced Tstat, checked/ cleaned fan limit switch and relay switch contacts. NO difference...help!
Old 12-02-10, 07:16 PM
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When you turn off the heat, are you doing so by turning the thermostat to "off"? If not, how are you doing it?

It sounds like you have either a sticking relay or a short in the low voltage. A make & model of the furnace might help. If there is a wiring diagram that would certainly help.
Old 12-02-10, 08:44 PM
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Hi welcome. This thread had another subject and you should start a new thread for this issue. Hopefully a moderator will bump this to the proper area.

Well Riecard I will what for the electricians to chime in bit I say enough Federal pacific panels burn houses to the ground then I can count on my fingers. Just do a google search and make your own judgment. Better yet here you go.

A Summary of the Federal Pacific Electric FPE Stab-Lok Panel Circuit Breaker Hazard, - FPE Repairs, Electrical Panel Replacement Electricians Directory for Stab-Lok Repairs

I wish I had a $193 dollar gas bill in the winter. Are you talking about a floor heater with a grate in the floor? They were very inneficient and unsafe as many from 1950 and earlier had no thermal coupling. Pilot goes out gas keeps flowing. Sound like you have many saftey issues and if it was me I would be very concerned.

Mike NJ

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