furnace won't start ???


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Old 03-03-03, 08:38 PM
W
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furnace won't start ???

Have a Lennox forced air gas furnace, 10 years old. pilot light on, fan blower unit works, Problem: when setting the setback thermostat to run heat, nothing happens. checked the breaker-ok, checked the batteries in the thermostat - ok, checked that electricity to furnace is on-ok, settings on setback-ok.

Is this an ignition issue, how do i fix it.

thanks for the insight.
 
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Old 03-03-03, 09:14 PM
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Please post replies here rather than in a PM. Everyone learns that way.

wendl:

If you only have heating and no airconditioning you can join the two wires together at the thermostat and see what happens. If nothing, then you can go to the furnace and short the w and r terminal. If still nothing you will need a multi tester to check the transformer, limit switch and gas valve.

If you are freezing and don't have a tester you had better call someone.
 
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Old 03-04-03, 05:06 AM
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furnace won't start

I have AC. Given that I crossed the wires at the thermostat, nothing.

Will look at the wires you suggested near the furnace. Thanks
 
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Old 03-04-03, 03:39 PM
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couple of thoughts

there could be a limit open, look for disc shaped devices with 2 wires and a button in the middle. depress the button. if it fixes it, call a tech, you have a problem. if you can locate a transformer chec to see if 24 volts is present on the secondary side. there may be a low voltage fuse in line, but i would doubt that since you have a pilot light. you do have a standing pilot flame at all times, right?
 
 

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