Hi,

My transformer blew on my Trane A/C. Tested the voltage and it's definitely fried (and charred--it got wet when the system iced up, but that's another story).

Anyway, got the replacement part (Trane Transformer 230v 21B800536P01 TRR1104 TRR01104) and lo and behold it's different--the high voltage side is the same--4 wires, I know which to attach--no problem.

But the low voltage side--where on my old one I have the yellow and blue coming from the coil, I have...nothing. Just the two coils. What's that about? Is this a common thing--do you just, I dunno, tap into the smaller coil somehow? I have noticed that one is not as taped as the big one, but there's no wire ends sticking out or anything. Do you cut two cables wires in the smaller coil to do it? I'm totally at a loss here and don't want to break it--4 days without a/c is getting old.

The old transformer has the plastic cap with the breaker, and it looks like it will snap to the new one just fine... but I can't for the life of me figure out how the wires from it tie in to the new transformer.

Thanks if anyone is familiar with this--surprisingly, there's nothing I could find online about it. All the info assumes you have the yellow/blue wires.

-Daniel