Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 07-16-2010, 05:46 PM   #1
Newbie
 
Join Date: Jul 2010
Posts: 2
Share |
Default

Just replaced fan motor and capacitor worked for 30 min now no go, need help!


I just spent the last 6 hours trying to problem shoot my HVAC and now Im at wits end.

Its an older (1972) 5 ton GE unit. The condenser will turn on but the fan motor wouldn't so purchased a new motor and capacitor installed the two. The unit worked perfectly for 30 minutes then the fan started to slow down and then completely stopped. Now the condenser will turn on and make some weird noises. I turn it off after 2 minutes or so in fear of it overheating. The fan will not turn on at all. I tried to jump it by spinning it myself but no go. The capacitor doesn't appear to be blown. Any suggestions? There are 3 additional capacitors and a fuse box all connected to the condenser. these all appear to be intact.

Faztaz is offline   Reply With Quote
Old 07-16-2010, 06:04 PM   #2
Member
 
Join Date: May 2008
Location: Near Philly
Posts: 2,032
Default

Just replaced fan motor and capacitor worked for 30 min now no go, need help!


Contactor might be bad?

bob22 is offline   Reply With Quote
Old 07-16-2010, 06:41 PM   #3
Member
 
Join Date: Oct 2009
Location: Nebraska
Posts: 2,362
Default

Just replaced fan motor and capacitor worked for 30 min now no go, need help!


Compare the new motor to the old. Same HP,amp draw and RPM ?
Marty S. is offline   Reply With Quote
Old 07-16-2010, 06:47 PM   #4
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 25,032
Default

Just replaced fan motor and capacitor worked for 30 min now no go, need help!


Also compare it to what the data tag says the motor should be.


Any chance that the fan blade was changed sometime recently?
beenthere is offline   Reply With Quote
Old 07-16-2010, 08:18 PM   #5
Newbie
 
Join Date: Jul 2010
Posts: 2
Default

Just replaced fan motor and capacitor worked for 30 min now no go, need help!


Yeah the motors are the same (ie Amps, H/P, RPM)
I actually jusy switched the blade from the old motor to the new motor.

I was inspecting the unit closely and noticed the insulation on one of the motor wires going to the capacitor was burnt and there were frayed wires. I think it was resting on the hot condenser when I buttoned everything up. I spliced the wire to remove the frayed end but still no go. Do you think the capacitor could have been damaged?
Faztaz is offline   Reply With Quote
Old 07-16-2010, 08:36 PM   #6
Member
 
Join Date: Jul 2008
Location: NW of D.C.
Posts: 5,990
Default

Just replaced fan motor and capacitor worked for 30 min now no go, need help!


Sounds like you haven't found the root cause of the first motor failure, but the only reason external to the motor/cap that I can think of for this would be low voltage due to bad HVAC connections or a bad connection in your house wiring.

For contactors/relays at rated current, less than 30 mV across closed contacts is good, more than 100 mV is bad.

Last edited by Yoyizit; 07-16-2010 at 08:53 PM.
Yoyizit is offline   Reply With Quote
Old 07-17-2010, 05:32 AM   #7
An old Tradesmen
 
Join Date: Oct 2008
Location: PA
Posts: 25,032
Default

Just replaced fan motor and capacitor worked for 30 min now no go, need help!


Its possible the cap over loaded from being shorted out.
beenthere is offline   Reply With Quote
Old 07-17-2010, 02:43 PM   #8
Member
 
hvaclover's Avatar
 
Join Date: Oct 2008
Location: Suburbs of Detroit Mi
Posts: 3,704
Default

Just replaced fan motor and capacitor worked for 30 min now no go, need help!


That GE is old. It uses a small mfd cap in series with the run cap to provide off cycle trickle voltage to keep the compresor rump warm.

Check the entire capacitor circuit for othe possible problems.
__________________
Just slow, not stupid.
hvaclover is offline   Reply With Quote
Old 07-17-2010, 05:55 PM   #9
Hvac Pro
 
Join Date: Nov 2008
Location: Winnipeg, Canada
Posts: 9,399
Default

Just replaced fan motor and capacitor worked for 30 min now no go, need help!


Only a "mature" tech like yourself would remember that one.

I will leave the rump size joke for later.

__________________
"Cut it twice and it is still too short".
yuri is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.