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Furnace doesn't come on, no matter where thermostat is set

\015 All power is on and breakers ok. Furnace was working fine and then just quit. I can get blower to work if I turn thermostat to ventilation only. Won't come on set on Heat. (No A/C or heat pump hooked up).\015\012Air from vent didn't seem to be as warm as usual just before it quit.\015

Answers :

This sounds like the relay switch on the control board may be bad. I just replaced a control board last week on a Carrier unit doing the same thing. The relays are built into the control boards. To fix this you must call a luxaire dealer and they can be found at www.luxaire.com. I will ask though, if you put the tstat into fan on instead of auto, does it come on? If it does, it could be a tstat issue. How you find this out is to remove the thermostat and expose the terminals. Take a small "jumper" wire and touch either one of the r terminals to the w terminal and hold it there. If the unit fires up with no problems, then it's the stat and not the board. Try jumping first and if it still won't come on, you know it's the control board. Good luck to both of you!

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Furnace doesn't come on, no matter where thermostat is set


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