Honeywell RTHL3550 Owner's Manual page 6

Alternate Wiring (Conventional Systems)
If labels do not match terminals, connect wires as shown here (see notes,
below).
C
X
B
If wires will be connected to both R and Rc terminals, remove metal
jumper.
Do not use C, X or B. Wrap bare end of wire with electrical tape.
Wiring—Heat Pump
If E and Aux do not each have a wire connected, use a small piece of wire to
connect them to each other.
L
Y2 W2
Y2 W2
Aux G O/B Y
E
G W
F W1
H
G W
R Rc
MCR31276A
6
Y R Rc
Y1 RH R
M 4
V
Y R Rc
MCR31274B