Powering The Thermostat - Honeywell TH8110U Installation Instructions Manual

TH8110U TOUCH SCREEN PROGRAMMABLE THERMOSTATS
Y2 RC
W2
S1
S2
3
OUTDOOR/INDOOR
TEMPERATURE
SENSOR
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
2
FACTORY INSTALLED JUMPER.
3 OPTIONAL OUTDOOR OR INDOOR REMOTE SENSOR. AVAILABLE
ON SELECT MODELS. WIRES MUST HAVE A CABLE SEPARATE
FROM THE THERMOSTAT CABLE.
Fig. 9. Typical hookup of heat only Series 20 system.
AUX
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
2
FACTORY INSTALLED JUMPER.
3 "O/B" TERMINAL SET TO CONTROL AS EITHER "O" OR "B" IN THE INSTALLER SETUP.
4
OPTIONAL OUTDOOR OR INDOOR REMOTE SENSOR. AVAILABLE ON SELECT MODELS.
WIRES MUST HAVE A CABLE SEPARATE FROM THE THERMOSTAT CABLE.
Fig. 11. Typical hookup of single-stage heat pump with no auxiliary/backup heat (1H/1C heat pump).

Powering the Thermostat

There are two different ways to power the thermostat:
• Batteries (three AAA alkaline).
• 24 Vac Common wire.
Wiring 24 Vac Common
Wire the common side of the transformer to the C screw
of the thermostat wallplate. When installing in a single
transformer system, keep jumper wire between the R
and Rc screws. When installed in a two-transformer
69-1700
CONVENTIONAL
2
R
W
Y
G
C
W B R
SERIES 20
MOTOR OR
TR TR
VALVE
HEAT PUMP
Y2
L
E
S1
S2
4
OUTDOOR/INDOOR
TEMPERATURE
SENSOR
Y2
1
R
W2
C
S1
S2
3
OUTDOOR/INDOOR
TEMPERATURE
SENSOR
1 POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
2 FACTORY INSTALLED JUMPER.
3 OPTIONAL OUTDOOR OR INDOOR REMOTE SENSOR. AVAILABLE
ON SELECT MODELS. WIRES MUST HAVE A CABLE SEPARATE
FROM THE THERMOSTAT CABLE.
M19899
Fig. 10. Typical hookup of cool only system
RC
2
R
O/B
3
Y
G
C
CHANGEOVER
VALVE
system, use the common from the cooling transformer to
connect to C screw and remove the jumper wire between
the R and Rc screws.
Inserting Batteries (Optional)
If not using a 24 Vac Common to power the thermostat,
install three AAA alkaline batteries (included) in the back
of the thermostat. Make sure the positive and negative
terminals are oriented correctly, as marked on the device.
See Fig.12.
4
CONVENTIONAL
RC
2
R
W
Y
G
OPTIONAL
C
COMMON
CONNECTION
FAN
RELAY
COMPRESSOR
CONTACTOR
(1C conventional).
1
R
C
OPTIONAL
24 VAC
COMMON
CONNECTION
FAN RELAY
COMPRESSOR
1
R
C
24 VAC
M19900
M19903