My thermostat wiring is old and unlabeled. Blue wire in wall connected to red on thermostat...?
In the wall, there are only 2 wires. Blue and white. The blue connected to the terminal on the thermostat with a red wire. The white wire in the wall connected to the white wire terminal on the thermostat. I checked the furnace, but couldn't find the
The blue wire should go on the R terminal and the white wire should go on the W terminal.
R is 24 volt hot from the furnace, W is the heating signal back to the furnace.
