DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   HVAC (http://www.diychatroom.com/f17/)
-   -   How should I trouble shoot a blower motor (http://www.diychatroom.com/f17/how-should-i-trouble-shoot-blower-motor-122719/)

jse 11-07-2011 07:39 PM

How should I trouble shoot a blower motor
 
I have an American Standard Freedom 90 furnace that decided not to work all the sudden. When trouble shooting the problem I found the contact for the MD-LO wire fried itself right off the I.F.C.. It's obvious i need a new I.F.C. but before I install one I would like to make sure the blower motor is working right so this doesn't happen again. How would i go about testing the different stages of the motor before installing the new I.F.C.? Or maybe someone can tell me where else to look for possible problems. Thanks!

Doc Holliday 11-07-2011 11:05 PM

You can test continuity/ohms through the wires. The higher the speed wire you test in ohms the less resistance it will show.

Yoyizit 11-08-2011 09:10 PM

Quote:

Originally Posted by jse (Post 766146)
before I install one I would like to make sure the blower motor is working right so this doesn't happen again. How would i go about testing the different stages of the motor before installing the new I.F.C.? Or maybe someone can tell me where else to look for possible problems. Thanks!

A fried wire sounds like it was caused by a mechanically loose connection. When current flows through the high contact resistance it gets very hot.

I just confirmed the blower motor operation on my furnace.
The schematic showed that the motor works on 120v and what pins controlled what speed.
I hooked up a suicide cord and fed the terminals with 120v, confirming that the motor worked before doing the considerable work of reinstalling it.
Once I knew it worked I checked resistance from each terminal to each of the other terminals so I'd have this info for the next time.


All times are GMT -5. The time now is 05:05 AM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved