Honeywell RTH7400 series - Quick Reference to Status Display; Current Day of Week; Current Inside Temperature; Current Time

7
Alternate Wiring (For Heat Pumps Only)
2
3
5
3 5
4
6
6
MCR32161
C
G
Y
O/B
RC
R
AUX
E
L
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.
5
6