TH8320U AND TH8321U TOUCH SCREEN PROGRAMMABLE THERMOSTATS
5 69-1706
Fig. 12. Typical hookup of conventional multistage two-stage heating and two-stage cooling
in a two-transformer system (2H/2C or 2H/1C or 1H/2C conventional).
Fig. 13. Typical hookup of single-stage heat pump with no auxiliary/backup heat (1H/1C heat pump).
R
NVENTI
NA
COOL RELAY 2 COOL RELAY 1
M19902
HEAT RELAY 1
FAN RELAY
HEAT RELAY 2
R
C
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
1
1
R
C
1
2
3
FACTORY INSTALLED JUMPER REMOVED.
OPTIONAL OUTDOOR OR INDOOR REMOTE SENSOR. AVAILABLE ON SELECT MODELS. WIRES MUST HAVE A CABL
SEPARATE FROM THE THERMOSTAT CABLE.
OPTIONAL 24 VAC
COMMON CONNECTION
MUST COME FROM
THE COOLING
TRANSFORMER.
3
OUTDOOR/INDOOR
TEMPERATURE
SENSOR
R
B
A
HEAT P
M
COMPRESSOR
M19903
CHANGEOVER
VALVE
FAN RELAY
R
C
1
1
2
3
4
4
OPTIONAL 24 VAC
MM
N
NNE
TI
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
FACTORY INSTALLED JUMPER.
"O/B" TERMINAL SET TO CONTROL AS EITHER "O" OR "B" IN THE INSTALLER SETUP.
OPTIONAL OUTDOOR OR INDOOR REMOTE SENSOR. AVAILABLE ON SELECT MODELS. WIRES MUST HAVE A CABLE SEPARATE
FROM THE THERMOSTAT CABLE.
OUTDOOR/INDOOR
TEMPERATURE
SENSOR