Wiring for 4H and 2C with dual fuel and 2 stage furnace

[peterg04]

Hi can someone explain me how to wire Nest Learning Thermostat (4th gen) with following equipment:

- 2 Stage Heating and Cooling Heat Pump w B-wire for Primary Heating and Cooling

- 2 Stage Variable Speed Gas Furnace only if the Heat Pump can not achieve or maintain let say 30F temperature

Can you explain where each wire should be connected to? and app configured?

I'm only confused on wiring 2 stages for the gas furnace as Y1 and Y2 will handle both stages of heating and cooling of the heat pump, so it mains W1 would 1stage gas heating and W2 would be 2nd sage gas heating, or some other configuration?

please explain what is the proper configuration?

thanks, Peter

[Patrick_Caezza]

@peterg04 

Post a picture of the wiring for the current thermostat.

[peterg04]

gF

[peterg04 · Accepted solution]

I wire thermostat this way, but not sure if it is correct.  Other picture is at 2 stage gas furnace.  

[peterg04]

In the above configuration does W1 activate heat pump or gas furnace?