Wiring; Terminal Designations; C Terminal; L Terminal - Honeywell PRO TH3210D Manual

Installation Guide
CAUTION: ELECTRICAL HAZARD. Can cause electrical shock or equipment damage.
Disconnect power before wiring.
%,-- _ _ _, ,=, ,=, _ _, _ , _%
l,J E AuxY G 0 L R B
/
Terminal
block
NOTES
C terrainal
The C (common wire) terminai is optional
when thermostat is powered by batteries.
L terminal
Heat pump reset. L terminai is powered con-
tinuously when thermostat is set to Em Heat.
Wire specifications
Use 18- to 22-gauge thermostat wire.
Shielded cable is not required.
Wiring
1 Ix)osen screw terminals, insert
wires into terminal block, then re-
tighten screws.
2 Push excess wire back into the
wall opening. Keep wires in shaded
area as shown at left.
Plug the wall opening with non-
flammable insulation to prevent
drafts from affecting thermostat
opemtion.
Terminal Designations
E Emergency heat relay.
Aux Auxiliary heat relay.
Y Compressor contactor.
G Fan relay:
O Heat pump changeover valve
energized in cooling.
L Heat pump reset.
R Power wire [_om secondary
side of system transformer.
B Heat pump changeover valve
energized in heating.
C Common wire fron3 seconda W
side of system transformer.