Gas furnace inducer motor has no power


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Old 11-06-18, 02:20 PM
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Gas furnace inducer motor has no power

Hi, My furnace stopped working recently and was blowing cold air only. The blower is working fine, so does the thermostat. I checked and found the inducer motor won't start due to no power in. I almost checked relative terminals on PCB and found no power there too. Please see the highlighted terminals in the attachment. I wonder if that can confirm that the issue is likely to be on PCB side.

Thanks!

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Last edited by PJmax; 11-06-18 at 02:30 PM. Reason: enlarged picture
  #2  
Old 11-06-18, 02:31 PM
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Welcome to the forums.

I enlarged the picture but there wasn't much detail to start with.
What is the part number on that board ?
 
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Old 11-06-18, 03:07 PM
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Furnaces usually have a ladder diagram attached along with the wiring diagram. Easier to see the sequence and interactions of the electrical/electronics. Could you post it if you have it?
 
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Old 11-06-18, 03:21 PM
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Start from the beginning. Is the furnace getting a call to run?
 
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Old 11-06-18, 03:28 PM
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Yes, it does get the call.
 
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Old 11-06-18, 03:32 PM
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Sorry about the blurry picture. Basically i traced back to the control board from the leads on the inducer motor and measured the voltage from there. I found no voltage reading at all. It looks to me it is an issue with the control board.
 
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Old 11-06-18, 05:00 PM
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If the blower is operating normally.... then the AC supply to the board is ok.
On a call for heat you should hear a relay close and the inducer start. If you don't get any 120vAC on the motor leads at that time then the board is bad.
 
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Old 11-09-18, 05:30 PM
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I tried a different board; it was the same. It got the call for heat and the blower started, But inducer motor didn't start afterwards. The wiring diagram for my furnace can be found here (page 35) - https://www.utcccs-cdn.com/hvac/docs...310A-45-16.pdf.

thanks!
 
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Old 11-17-18, 06:46 AM
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Same Problem on a York

Sorry I can,t find where to start a new Thread- I installed a new Control Board several months ago-it worked fine but I didn't have it mounted correctly, it started to blow fuse's. Acouple of days ago, nothing, No LED light, nothing. Power was coming into the board, as I tested the connection, but no power to the board. I changed back to my old board, still no power to the board. No blinking LED light.
I am lost, what do I check in this situation. I am thinking I need a new board, but would like someone to confirm.
Thanks Bilhar
 
  #10  
Old 11-17-18, 07:43 AM
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You need to pull out your meter and start checking for power and shorts.
I don’t know what you mean when you say the board wasn’t mounted correctly, or why you’d leave it that way, but such a thing can damage the board.
There are some boards I’ve seen that use the mounting feet as a ground source. And will not work without them secure.
 
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Old 11-17-18, 11:17 AM
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The new board was not the same as the old one, mounting holes did not line up, I am 81 years old and got tired of trying. I don't know where to start.
 
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Old 11-17-18, 11:29 AM
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Is the board getting power?
The board needs to be secured.
 
 

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