On 4/9/2011 10:22 PM, Phil Allison wrote:
"robb"


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

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

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).


** From the damage to the tranny visible in the photos - the primary has
developed an internal short ( due to insulation failure) and since there is
no fuse link in series, the resulting current was high enough to make an
exposed wire leading to the terminals explode.

An internal short could develop due to heat alone because of an overload on
the tranny - but this requires a fault to exist on the secondary side which
seems not to be the case.

Oh my gawd, someone agrees with me. Looking at the picture says a lot.
Burnt on the primary side, looks like new on the secondary. And this
is the third transformer with an open primary!


I don't know about a the 1uF cap, seems way too high so I'll delete what
was below and pretend I didn't see it.