About to install a new Honeywell RTH6300B thermostat. I have 5 wires coming from the wall...green, yellow, white, red and blue. Old thermostat had connections for W, RH, B, RC, G, O, Y...(Old thermostat was White Rodgers model # 1F86-244.) New Honeywell RTH6300B thermostat has connections marked G, W, Not Used, Y, R, Rc.
I can understand Y=yellow, W=white, G=green, and R=red....what about the blue wire? New Honeywell thermostat has no terminal labeled B.
P.S. Old thermostat (White Rodgers) had a red metal jumper on RH and RC with the red wire from the wall connected to the RC terminal.
New Honeywell RTH6300B thermostat has a metal jumper on R and Rc.
Any help would be greatly appreciated.