Hi All,

I have a TRANE BAYHTR1408 (TWE030C14FBO) heating and AC unit. The old connection wires were as follows

wire color = letter

red = R
yellow = Y/Y2
green = G
blue = C
white = W/W1
orange = O/W2

I am trying to figure out how to connect these wires to the new Honeywell RTH7400D?

The new letter options are as follows:

C, G, Y, O/B, RC, R, AUX, E, and L for the heat pump option

C, G, Y, W, RC, R W2, and Y2 for conventional option



Any help would be appreciated.

Ash

Looks like you have a heat pump due to the orange wire that tells the reversing switch in the outside unit what to do.

wire color = letter - new thermostat

red = R - R/Rc jumpered
yellow = Y/Y2 - Y
green = G - G
blue = C - C
white = W/W1 - Aux and jumper it to E (emergency)
orange = O/W2 - O