What all those letters mean on your thermostat’s wiring Thermostat wiring heat wire honeywell wires room standard hvac connection american reference trane chart two pump color heating air thermostats Thermostat wire reference chart:
What All Those Letters Mean on Your Thermostat’s Wiring - iFixit
Thermostat wiring diagram mean letters wire 2wire only where ifixit thermostats which goes
Thermostat Wire Reference Chart:
What All Those Letters Mean on Your Thermostat’s Wiring - iFixit