Zen Thermostat from Mercury


#1

hi, I would like to use the Zen thermostat just as a relay for a fireplace.
old wiring was through an old mercury stat, installed zen but im sure I have the wiring wrong,
There is only 2 wires you touch them together and fireplace comes on…

does anyone know what labels they should be in?


(Kirk Hilzinger) #2

Red is +24VAC. RH is the heating side. RC is the cooling side. Typically, you only use the RH.

W1 is typically “Furnace”. So that is why it calls for heat. W1 and W2 are used if you have a dual-stage furnace.

With most smart thermostats, you also need a Blue C wire, which is -24VAC, to power the thermostat. Or, the thermostat runs on batteries.

Y1 and Y2 are Yellow and those are used for A/C, two being for if you have dual stage.

G is Green for fan.

Hope that helps.

But, most code will not allow you to turn on or off fireplaces unless someone is physically there. Keep that in mind.


#3

it all works now, in case anyone needs to know, the thermostat needs to be set to 10A in the first config screen this will tell the thermostat that its dealing with a fireplace as per zen support team,
google home now turn fireplace on and off !!!