I have a 15 year old gas furnace and a 15 year old programmable Honeywell thermostat, with heat and air.
The furnace is randomly failing to come on (heat or fan), until I turn the master furnace switch off then on. Even if I set the thermostat temp above the current temp.
The furnace then ignites normally, runs till the house reaches the thermostat temperature, then shuts off normally.
The repair man could find nothing wrong. He was a good knowledgeable guy but because when he was here everything worked, he had to leave without fixing anything. He checked limits, CO2, etc. All was fine. NO cracks, etc.
There is a hum from the furnace when it wont start. I then turn off the master and the hum goes away. Switch on, furnace starts.
Anyone have any theories? Could it possibly be the thermostat?
2007-12-01
10:57:45
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7 answers
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asked by
cornmanz
1