I have a standard 2 stage gas heater and single stage electric cooling system. I am changing the thermostat.

The T874C1018 has a red wire that is jumpered from Rc to Rh and a white wire that is connected to W1. Yellow goes to compressor contactor and green is the fan relay.

Hooking up the current 4 wire setup:
Yellow to terminal Y,
Green to terminal G
Do I jumper the red wire from terminal B to O
Do I connect the white wire to terminal labeled Aux or terminal R