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Trane XL90 Gas furnace wont run

5 posts in this topic

Hi folks. I'm back. This time it's the furnace.

I've got a Trane XL90 gas furnace with a XE1000 heatpump installed for cooling. They're controled by a Honeywell Chronotherm III thermostat.

The problem is the furnace wont start. The thermostat calls for heat and I hear the transformer buzz but that's it. No fans or blowers. The filters are clean. I have 26 volts between R and G at the thermostat.

I can turn the fan to manual and the fan runs and blows air so I know that fan works.

I can also turn the thermostat to cool and the heatpump and fan works perfect.

I've also put new batterys in the thermostat to eliminate that issue.

Are there any suggestions you might have for me on what to look at? I've faily clever and can fix things but this is my first attempt at a furnace.

Thanks a bunch..........john

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Need appliance parts? Call 877-803-7957 now!

Check to see if the furnace's condensate drain is clogged if the blower is running but there is no heat. Remove the clamps to the trap and drain the trap outlet. Flush out any blockages and reinstall the trap clamps

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... I've got a Trane XL90 gas furnace

model number ?

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Thanks guys.

Just for clarrification, the blower is not running. It only runs if it turn the thermostat to "fan" to circulate air. It doesnt run when I turn the thermostat to "heat". The thermostat calls for heat as I can here the click and a buzz from the transformer but nothing happens.

Sorry, I forgot to get the model number. I'll get that tonight.

Thanks again for the help

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Woohooo! I came home to get you the model number and messed with it for a while. I began to notice that it would call for heat and the transformer would buzz but that was it. BUT, what I also noticed was when I went to turn it off (no sense in the transformer just buzzing) it would sound like a fan would just start to come on and then shut off.

Cleaned the connections in the thermostat and my wife worked that switch back and forth and TADA!!!! Works like a dream.

Sounds like I'm gonna need a new thermostat someday.

Thanks guys..............

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