I’m using a 1st generation Google Nest Thermostat. Above are pictures of
(1) the original thermostat wiring - did not use jumpers as per Google. 1st gen only has 6 terminations: W C Y G R OB*
(3) Current configuration of downstairs - not configured for heat pump. Only way I can get heat in this zone.
(2) screenshot of the technical manual thermostat wiring - the air handler model I have TEM4A0B24S21SAA but the only TM I could find was for TEM4A0B24S21SB, not sure if there’s too much of a difference.
(3) the side of the air handler - looks like the thermostats are daisy chained?
Soon as one zone (upstairs and downstairs respectively) starts working; I don’t get heat in the other zone. The outside unit for the heat pump would only would kick on for upstairs zone.
That was a lot,
Hope y’all can help,
Do you have 2 Nests?
The wiring looks like a basic heat pump.
Not sure how the 2nd tstat is wired into the system.
How does it change zones is there a zone damper in the ductwork that changes the air flow?
The wiring info is usually on a decal on the back of the door of the air handler and also outside another decal if you take off the cover where wires enter the unit.
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