On 4/9/2011 12:19 AM, Steve Turner wrote:
On 4/8/2011 10:16 PM, Tony Miklos wrote:
On 4/8/2011 8:52 PM, Steve Turner wrote:
A continuation of the "Why does the 115V-24V transformer keep blowing
on my Trane XB80?" discussion I started on 04/02/2011.

Yep, My A/C unit blew another transformer. Pictures (and wiring diagram)
he

http://www.flickr.com/photos/bbqboye...7626457562742/

Trane's manual for the unit is here (for perhaps better viewing of the
wiring diagrams that I also copied to my above flickr site as jpg
images):


http://www.trane.com/webcache/un/fur...7_04012009.pdf




As you can probably see in the pictures, there is visible charring of
the 115V leads going into the transformer, and of course the 115V
circuit is open (again).

Three times it fried the primary? I'd guess it's getting 240vac at
times. It's
very unusual for the primary to go bad from a short on the secondary
side, and
the picture shows that the secondary wasn't overheated like the
primary was.
Where's all those electricians talking about an open neutrals when you
need
them? If it measures 120vac tie a light bulb into the primary side and
leave it
where it can be seen. Have the family let you know if it ever gets
brighter
than normal. Or better yet, call a pro.

That very thought crossed my mind, but I'm not sure how that could
happen. The unit is on a dedicated 115V circuit tied to a single-pole
breaker. Where would the possibility exist for the neutral to become
hot? In the breaker box?


It happens all the time.