Hi,

I got a problem with main blower in gas furnace. I've checked this site, but didn't find an answer.

Symptoms: Sometimes it starts and stops when burns work or don't start at all. Relay clicks to start blower in 30 seconds after burner started, but blower doesn't start or stops and then tries to start again. And interesting, when I turn heat off on termostat, then blower starts and works for about 3 minutes as expected.

Furnace details: Model: Goodman GMP 075-3 '95. It has hot surface ignitor and electronic timers to start and stop main blower.

All parts are original. Air filter was replaced. Sequence works as expected until main blower (inducer fan on/off, burner on/off.) Squirrel cage can be turned by hand easily with no power. I've tried to test capacitor with ohmmeter, it always shows infinity.

Any advise will be appreciated.

Thank you.

Try switching the thermostat fan switch from Auto to ON, will it stay running now?

Tried: blower seems to run Ok in ON position.

It looks like there was a problem with run capacitor.