am trying to hook up the wyze thermostat to a very old Williamson heat pump system with a mercury switch thermostat.
I know what all the signals are in my system since I have a complete diagram of all the control wiring.
But your descriptions of each pin-out on the thermostat are minimal at best.
here is what I have.
My letters are not going to be same as newer models in most cases therefore the description of each.
W1 Reversing valve in heat pump
W2 Backup electric heat
G Fan
R 24vac
X 24vac com
C Compressor
K Emergency Heat
can you correspond each signal to your plate
Rc Y1 Y2 O/B G
Rh W1 W2 * C
A good description of each of your connections would eliminate the grey area.
Maybe fellow user @speadie or one of your other fellow users will chime in to answer your questions, but this is a user-to-user forum and not a support site for Wyze. Wyze has a presence here, but not the support arm of Wyze. The best way to contact them is by phone at (206) 339-9646 Monday - Friday 4 am - 8 pm PT and Saturday 8 am - 4 pm PT. [note due to typhoon Rai recovery, hours will be 6 AM - 6 PM PT for the next 5 days at least]
To match your wiring: (pinout changes slightly depending on the device that is being controlled)
O/B= Reversing valve in heat pump
W1= Backup electric heat
G= Fan
Rc= 24VAC
C= 24VAC Common
Y1= Compressor
*= Emergency heat.
During setup, tell the wyze app that your “old thermostat” uses the following wires: Rc, C, G, Y1, W1, E, and O/B.
When you test the first stage (heatpump) heating and cooling, if they are reversed, go to settings>advanced>swap heat and cool.