Wiring appears to be correct, however would could possibly help with the
nest is by adding a C or common wire from the air handler to the nest.
From the pictures sent I can't see, other than no common wire, for there
to be an issue. That would be a c...
If the stat is defective i believe they have a 3 year warranty, however
before going through taking it off the wall and heading to the retailer
to exchange the stat. At the condenser you said the if you jump the O &
Y the change over valve switches o...