Well, mystery solved! After compressor check I ended up swapping capacitors (I have a similar second unit) - no joy, swapping the whole control box
- no joy, swapping sensors - nothing, something just didn't make sense. I thought about Sailmonkey comment "direct at the terminals", and followed the wires to compressor terminals as earlier I have checked the voltage coming out of control box
since the compressor is not so easily accessible. There you have it - nothing. Well, it turned out to be a no continuity in common ground! How does a straight wire go bad I don't know, but it sure was a simple fix after 2 days of head
scratching. Thank you for your input!