PRO TH3110B Non-programmable Digital Thermostat
5
Installation Guide
4
Wiring
1
Loosen 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.
3
Plug the wall opening with non-
flammable insulation to prevent
drafts from affecting thermostat
operation.
Terminal Designations
W
W Heat relay.
Y
Y Compressor contactor.
G
G Fan relay.
O
O Heat pump changeover valve ener-
gized in cooling.
R
Rc
c Cooling power. Connect to
secondary side of cooling
system transformer.
R
R Heating power. Connect to
secondary side of heating
system transformer.
B
B
Heat pump changeover valve ener-
gized in heating.
Terminal
block
NOTES
R & Rc terminals
In single-transformer system, leave metal
jumper in place between R & Rc. Remove
metal jumper if two-transformer system.
Heat pump systems
If wiring to a heat pump, use a small piece of
wire (not supplied) to connect terminals
W
and
Y
.
Wire specifications
Use 18- to 22-gauge thermostat wire.
Shielded cable is not required.
Keep wires in this
shaded area
CAUTION: ELECTRICAL HAZARD.
Can cause electrical shock or equipment damage.
Disconnect power before wiring.
Wiring
Typical 1H/1C system: 1 transformer
Typical 1H/1C system: 2 transformers
Power supply. Provide disconnect means and overload protection as required.
Factory-installed jumper. Remove for 2-transformer systems only.
Use either
O
or
B
terminals for changeover valve.
Use a small piece of wire (not supplied) to connect
W
and
Y
terminals.
Set fan operation switch to
Heat Pump
(see page 6) and configure for heat pump (see pg. 8).
Remove jumper
Wiring diagrams
Typical 1H/1C heat pump system
Typical heat-only system
Typical heat-only system with fan
Typical cool-only system
