I have a Trane XE80 gas furnace. The purge motor and burner go on, but main motor won't run. LED flashing light flashes continuously when burner is on however, when the burner shuts off, the LED light flashes 4 times at an interval. I tried to look for a reset button on the main blower motor but couldn't find one. Can you help me?

There is no reset for the blower. Try turning the fan on at the thermostat, and cycling the heat. If that works, you have lost a speed leg in the motor, and need a new motor-running it like this will work as a temporary fix-and I stress TEMPORARY. (I currently have a client with the same issue, and this is how he's getting heat until I can get the board in my hands).

If that doesn't work, troubleshooting blower and related components is in order. Fan relay on control board may have failed, or it could simply be a motor or capacitor problem. Cycle furnace, check for 110v between Common and the Heat terminal of the fan board. If the fan board is providing 110v, the problem is in the motor or capacitor-if not, it's the board. Unless you have a cap checker, the easiest way to check a capacitor is to change it (less than $10). If that fails, you need a motor.

Thanks for your advice. I turned on the thermostat fan and it works. However I had to rotate the motor fan manually to start the main blower motor. Do you think there is a problem with the control board or capacitor?

It's possible the capacitor is bad-more than likely though, you'll need a motor. The control board is probably fine-it has the fan relay-which seems to be doing its job.

The capacitor is an easy change, but break out the tools if the motor needs replacing. It's fairly straightforward for the mechanically inclined-but a blower wheel seized on the shaft can be daunting if you don't have the means to take care of it.

Capacitors are easy to check if you have an ohm meter. Short it out and remove one terminal. Check with the meter. It should start fairly high and climb off scale. Anything else, and you have a cheap, easy fix.

Until you get a new blower motor, keep the fan on "Auto". This will run the fan constantly. At least you will have heat.

He means to turn the Fan switch on your thermostat to "On", not "Auto". I would be leary of running an overheating motor full time though. Use your best judgement-but don't delay the repairs until meltdown, as it will only cost you more to repair at that point.

To All,

Thanks for the advice. The blower motor went bad and has to be replaced. Help is on the way.

Thanks Again.

What size generator in amp range would I need to run the furnace of my Trane xe 80?