Heating, Air Conditioning, Fridge, HVAC/furnace inducer motor


QUESTION: Hello I have a Weather King furnace 90+ that wont start. The model is 90TJ07EFS01-EB I put a new inducer motor on but am still having problems. When I set the thermostat to heat the motor wont start. I can spin the inner wheel and it will run but it will not start on its own. The control board blinks twice for a open pressure switch. I have made sure the hose was clear and  it does move when I blow into it. I also made sure the vent tube was clear. I had a digital thermostat so i switched it back to a old school dial one. When I hold the door switch down the control board clicks but nothing happens.  I was wondering if there was a way to test the blower even though it is new and where to go next. I was thinking its something on the control board but I hate to randomly replace things if there is a way to test. I'm not to sure how to test voltage into blower to see if its getting the correct signal. Thank you for any input

ANSWER: Hi Jeff, I can't find much info on your furnace. Can you send me a close up pic of the wiring diagram? When you spin the wheel are you talking about the inducer?

Try tracing the wires from the inducer motor back to the control; board. Pull those wires off. Test those pins with your meter. You should have 120V when the tstat is calling for heat.

Let me know what you me know what you find. JIM

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QUESTION: yes I was talking about spinning the wheel on the inducer. It spins freely does not seem to be a problem. I tested the voltage at the pins on the control board, no voltage checked the wires coming out of the door switch getting 125 volts when calling for heat. Guessing this means the control board is bad? I will try to attach a picture of wiring

Hi Jeff, I found some more info on your furnace. Turns out you inducer motor uses a capacitor. Did you replace the cap when you replaced the motor? I think the cap is bad, that's why when you spin it starts running. That's a sure sign the cap is bad.

Let me know, JIM

Heating, Air Conditioning, Fridge, HVAC

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Jim S.


I can answer questions on gas or electric furnaces, ac units and heat pumps. I don't work on boilers,chillers,or home appliances.


I have been in the HVAC trade for over 35 years. For the past 15 years I have owned my own business. I am semi-retired so I can answer questions in a timely manner.

I attended trade school for 5 years on weekends and evenings. This was very hard to do, but well worth it!

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