The induced draft fan is not running. Is that what you mean by "exhaust fan"?
I'm not an HVAC tech but I have electrical experience and I've done some reading. I have a service manual for the unit. It says the first thing that should happen after the thermostat calls for heat is for the ID fan to come on. But that's not happening. So I guess the fan motor could be bad. I see that it has a hall sensor to detect when the motor is running but if motor is not turning then the sensor wouldn't detect any rotation I assume.
Last night we had a wind storm at my house. The power flickered briefly and then went off for a few minutes. I wonder it the motor got damaged.
I checked the air conditioning function of the unit. That's works ok.
I'm thinking about removing the fan to see if I can make it run by applying power directly but at this point I'm not sure what voltage it takes to run the motor.
Anyway, I'll give you a chance to respond.
We have 2 choices..either the motor is compromised...or the circuit boad is not sending inducer power.we need to see if 115v is sent to inducer.no 115v = bad circuit board115 present = bad motorBilly
I see what you mean. I have a meter and I can measure the motor voltage if I can find a place to attach the leads, but I don't know if the control computer sends power to the motor continuously or just momentarily. If the motor fails to start does the computer continue to apply power as long the thermostat is calling for heat?
I guess the first thing to do is to see if there's any power at motor when the thermostat is calling for heat.
I jiggled the motor wires at the control board terminals. I was looking for a place to attach voltmeter leads. Then I decided to go get some alligator clips to attach the leads (I don't want my hands inside the unit when I turn the power on). While looking for the alligator clips I turned the power back on to the unit. To my surprise the unit came on!
I've cycle the thermostat on/off several times and it works perfectly.
So for the moment I guess I'm back in business. But I don't have a real warm fuzzy feeling (no pun intended).