On 4/8/2011 7:58 PM, David Nebenzahl wrote:
On 4/8/2011 5:52 PM Steve Turner spake thus:

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). If you didn't see my first thread, this is the third transformer the
unit has blown. In the previous discussion, it was discussed that perhaps the
first one just blew because of old age (6 years), and the second blew because
it wasn't a proper replacement (poor quality, made in China, etc.). This
third unit is most certainly a proper replacement, and it's most certainly
indicative of a real problem I have somewhere else in the unit. I didn't see
any such charring on the previous two units, at least not like this.

How 'bout installing an in-line fuse next time you replace the xfmr? I'd put it
on the secondary side. That way, if there is an overload, the fuse will blow
instead.

Thinking maybe I should spring for a transformer with a manual reset, like this
one:

http://www.pexsupply.com/White-Rodge...unt-14937000-p

Would that protect me from having to replace the damn transformer every time?
It looks like the circuit breaker is on the 24V output side; I'm a little fuzzy
on how that would protect the input side of the transformer...?