new home, original thermostat wiring (above)
new home, original heat pump wiring
I have a heat pump from 1989 and I had some challenges wiring. There was a W, Y, C, R & G wire on my old thermostat and I spent an hour+ with Google support trying to get it right, unsuccessfully. Funnily enough, this is my second nest thermostat setup on this exact same heat pump from when I lived in another unit in the same building so I recreated that setup and got things mostly working. I ended up with separate Rh & Rc wires in addition to the O/B, Y, C & G wires. I had to configure the B heat pump setting to get heat and cool to come out appropriately.
old home, previous nest installation in previous unit with same heat pump
old home, previous heat pump wiring with nest working (minus power on the G fan)
old home, N6 error on the old nest in the old unit with the same heat pump
new home, nest wiring setup
new home, new heat pump terminal wiring (yes, I modified it to match the old, working setup since it's the same machine and control board)
heat pump side panel info
My problem is that when the heat cycle starts, it won't stop even after it hits the target temperature and the screen goes black. I can set it to the "off" mode and it still won't stop. The only way I've found to get it to stop without throwing the breaker is to start a cooling cycle.
When I go to the settings menu, and run through the equipment heating test and wait long enough to hear the heating engage, verify heat is coming out, and select "done" it continues heating.
When I engage cooling it stops heating, yay! As soon as cooling hits it's target temperature, it stops as expected.
Interestingly, there's an error on the original nest in my old unit that the G fan wire isn't getting current but the wiring in the furnace is the exact same. I disconnecting the G wire and it didn't make a difference with the heating cycle. I also reconnected my old (Honeywell) thermostat, adjusted the wiring back and with the old setup the heating cycle ends as expected. I tried to get the nest working with the old control board wiring to no avail. First I'll get a E80 error with no power on the C wire, I read through the manuals I can find online and I've tried a dozen or so different wiring combinations but nothing else, that I've tried, gets as close as the same configuration on the old setup.
Thanks for reading, thinking and hopefully helping me solve this conundrum!
Thoughts!?
