Heat pump: burning transformers
#1
02-03-17, 03:47 PM
Heat pump: burning transformers
I have an older york hvac system. Installed in 97, outdoor unit is newer from 2015 r22 system. 2 weeks ago came home, no heat. Replaced 5a fuse on control board. Blew again. Put a 7.5 on and it ran fine for a few weeks. Came home again to no heat. Transformer inside the indoor unit was fried. Here is where things get weird. Replaced transformer. Kicked heat on and the ttansformer started to smoke. When I take the yellow compressor control wire off the control board, everything runs fine but its using emergency heat only, place yellow wire back on board and the whole system shuts down, transformer buzzes and starts smoking. I tried using another wire, same issue. Replaced the whole control board. Same issue. Bew tstat, no heat at all. I can go outside and push in the contact switch and the outdoor unit runs fine. Ive had 3 hvac techs look at it and charge over 500 dollars so far to no avail.... suggestions ?
#2
02-03-17, 03:55 PM
Group Moderator
Welcome to the forums.
Hmmmmmmmm........ maybe there's a reason why they use a 5A fuse for protection.
I wouldn't even use a 5A..... I'd use a 4A fuse.
If the problem occurs when the compressor is running...... the contactor is bad.
If this is a Rheem or Ruud unit..... my answer will change so let me know.
Hmmmmmmmm........ maybe there's a reason why they use a 5A fuse for protection.
I wouldn't even use a 5A..... I'd use a 4A fuse.
If the problem occurs when the compressor is running...... the contactor is bad.
If this is a Rheem or Ruud unit..... my answer will change so let me know.
#3
02-03-17, 04:54 PM
Member
A model # would help,also I assume this is a York heat pump if it goes into emergency heat mode,correct?it could be the reversing valve.
#5
02-03-17, 07:09 PM
Group Moderator
If your thermostat uses an O wire and not a B wire...... I would change the contactor on the outside condensor. It has a 24vac coil on it and from what you are describing and the timing... that's the problem.
