Trying to replace old ghetto theromstat with nest. Took a look at the air handler and this is what I have.
I know it's not a great pic, i didn't see labels on terminals until I looked at pic later. Can't find a wiring diagram for this trane handler from 1994. I see w1, w2 and what looks like R, O, B.. Obviously I need to go back and take a better look but is it fine to just rewire it straight to nest or do I need to investigate further? I see OB on nest but O and B looks like separate terminals here. Not sure about w2 either.
View attachment 288111
View attachment 288112
You've got everything you need there for a Nest, but you're going to have to do some experimenting. A signal tracer would help so you can figure out what the wires are when they get back to your air handler. That would make life easier.
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