14
Alternate wiring (heat pump system only)
Leave metal jumper in place, connecting
R
&
Rc
terminals.
If your old thermostat had both
V
and
VR
wires, stop now and
contact a qualified contractor for help.
If your old thermostat had separate
O
and
B
wires, attach the
B
wire to the
C
terminal. If another wire is attached to the
C
terminal, stop now and contact a qualified contractor for help.
If your old thermostat had
Y1
,
W1
and
W2
wires, stop now and
contact a qualified contractor for help.
If
L
terminal is used,
C
terminal wire must be connected
(contact a contractor if there is no
C
wire).
If
E
and
Aux
terminals do not each have a wire connected, use
a small piece of wire to connect them to each other.
Alternate wiring (conventional systems)
Remove metal jumper connecting
R
and
Rc
only if you must connect both
R
and
Rc
wires.
If your old thermostat had both
R
and
RH
wires,
remove metal jumper. Connect the
R
wire to the
Rc
terminal, and the
RH
wire to the
R
terminal.
If your old thermostat had only 1
C
or
C1
wire, connect it to the
C
terminal. If your old
thermostat had 2
C
or
C1
wires, wrap each
separately with electrical tape and do not
connect them.
C
G
Y
W
RC
R
W2
Y2
Y2
W2
W
Y
G
MCR32160
R
2
Rc
2
C
3
Conventional system
Connect wires: Heat Pump
1. Match each labeled wire with same letter on new thermostat.
2. Use a screwdriver to loosen screws, insert wires into hole under
screw, then tighten screws until wire is secure.
3. If
E
and
Aux
do not each have a wire connected, use a small
piece of wire to connect them to each other.
4. Push any excess wire back into the wall opening.
Labels don’t match?
If labels do not match letters on thermostat, see Alternate
wiring (heat pump system only)
Heat pump
2
3
5
3
5
4
6
6
MCR32161
C
G
Y
O/B
RC
R
AUX
E
L
5
6
Wiring Notes
MCR33552
Aux
E
L
C
G
Y
O/B
RC
R
HEAT PUMP
Y
G
R
Au
x
O
HEAT PUMP
