I have a new home with a single heat pump and dual zone (upstairs and downstairs) being controlled with a Honeywell HZ322 controller. I bought two Nest Thermostat E's and based on my current wiring, the compatibility checker said they were compatible. The new Nest E's only have 6 wiring connections and I have 7 wires coming out of the wall.
I think the issue is with The Aux and Emergency heating wires. I have one for each, see black and white in the photo. The nest website says to use emergency heat wire to the W1 connection and it will use it to do emergency and aux heating. I tried that last night and was having a lot of problems. I think with the HZ322 controller, this setup will not work. I'm afraid with the emergency wire connected to W1, when trying to use Aux heat, the controller will think Emergency heat is selected and will turn off the heat pump.
At this point, i'm considering either buying two Nest gen 3's or using the Auxiliary wire on W1 and not having Emergency heating as an option at the nest. The controller has a backup emergency heating pushbutton on it.
Any opinions? https://imgur.com/2kTi9xM https://imgur.com/DrwQJtb
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