Thermostat install help with zonefirst

Hi everyone!

I’ve installed so many of these things for my friends and family and have seen all sorts of weird setups, but my new house has me stumped.

I have a 2 stage heat pump. The wiring leaves the unit and goes to a zonefirst h32 controller which opens and closes electronic dampers. I’m replacing one of the thermostats in this system with a wyze.

I thought I could simply remove the wiring from the old thermostat and plug it into the wyze and I would be good to go. It’s a brand new system.

The original thermostat had:
Blue wire on C
White wire on B
Orange wire on W2 (jumpered to W1)
Red wire on R
Yellow wire on Y
Green wire on G

I wired the white to o/b, the red to RC, the orange to W1 and the rest were self explanatory.

Upon testing the system, the blower would come on, but I would only get room temperature air.

I decided to check the wiring at the zonefirst unit…

Here’s where things got interesting (and definitely confusing for me).

The blue wire from the thermostat bypassed the zonefirst board and was wire nutted to the main units’s C wire.

The orange wire from the thermostat bypassed the zonefirst unit and went to another wire nut but I struggled to see where in the main unit it ended up at.

The white wire went to a terminal labeled W/OB

Yellow was still Y
Green was still G
Red was still R

Does anyone have any thoughts?

Thanks in advance.

I need to see where that orange wire goes when it reaches the blower and heat pump.

In the meantime, if you just want to get heat running, you might try going to advanced settings on the wyze and switching the valve logic advanced>swap heat and cool

Thanks. While I investigate the orange wire, can you explain what the swap heat and cool function does?

It reverses the logic on the heatpump reversing valve. Often when people say a heatpump is outputting room temperature air, it is because the reversing valve is running in cool mode with the heat strips enabled. Reversing the logic means that when the heatstrips are enabled, it will be running the reversing valve in heating mode, so you should get actual heat.

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The orange wire bypasses the zonefirst board, and gets wire nutted to a white wire with a blue stripe which ends up on the W2 connection on the main unit.

Do you have a heatpump?

Yes. I have a 2 stage heat pump.

Then I’d expect the orange wire to go to the heatpump, not to W2

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The original thermostat was a Pro T721 and it functions properly (firing just the heat pump on stage 1 and the heat pump and heat coils on stage 2). This is how it was wired.

Hmm. interesting wire color choices.
Either way, the way you have it hooked up to the wyze should work, but you might need to reverse the logic of the reversing valve with the “swap hot and cool” setting (or whatever it’s called, I don’t have a heatpump to see the exact language wyze uses, just know it’s something along those lines.)