Thomas and DLane thank you for great responses. I resolved the issue, but I do credit you for steering me to the solution. To answer Thomas’s response, I decided to reattach my old Hunter controller to see if the ‘C’ line is broken inside (could not find a voltmeter) and a few zones, just to check a theory. Yes, all the zones were working before Rachio install, and all zones worked after Hunter was reinstalled the 2nd time. But I noticed how nicely wires are being held by the ‘pinch screw’ connector, while Rachio uses the ‘WAGO-esque’ connector. Rachio connectors are holding nicely; tugging on them, they don’t come out. I took fine-grit sandpaper and cleaned up oxidation on those solid copper lines; they did not look bad, but just in case. Rookie mistake, should have checked that right away; now all the zones are running perfectly. I do think cleaning common was what fixed it, since none of the zones worked before cleaning. Cheers!
