Installation Guide
P/N 041-338 Rev. A 4 69-2655EFS—01
Wiring
See [notes] below
[1] Power supply. Provide disconnect means and overload protection as required.
[3] Connectionto24V common at the transformer is required.
[5] O/BsettocontrolaseitherOorBininstallersetup.
[6] IfLterminalisused,24V common (terminal C) must be connected.
[7] Heatpumpreset(poweredcontinuouslywhenthermostatissettoEm.Heatmode;systemmonitor
whensettoHeat,Cool,orOFF).
[9] See page 14 for more details.
Terminal Designations
Conventional Terminal Letters:
R Heating power. Connect to secondary
side of heating system transformer.
Rc Cooling power. Connect to secondary
side of cooling system transformer.
C Common wire from secondary side
of cooling transformer (if 2 transform-
ers). [3]
W 1st stage heat relay.
W2 2nd stage heat relay
Y 1st stage compressor contactor.
Y2 2nd stage compressor contactor.
G Fan relay.
K OptionalTHP9045WiringModule
Terminal [9]
S1/S2 Optional remote sensor
Heat Pump Terminal Letters:
R Heating power. Connect to secondary
side of heating system transformer.
Rc Cooling power. Connect to secondary
side of cooling system transformer.
C Common wire from secondary side of
cooling system transformer. [3]
Y 1st stage compressor contactor.
Y2 2nd stage compressor contactor.
Aux/E Auxiliaryheatrelay.
G Fan relay.
L Heat pump reset (powered continu-
ouslywhenSystemissettoEmHeat;
systemmonitorwhensettoHeat,
Cool or Off).
O/B Changeover valve for heat pumps.
K OptionalTHP9045WiringModule
Terminal [9]
S1/S2 Optional remote sensor
Wiring guide—heat pump systems
1H/1C Heat Pump (no auxiliary heat)
Rc Power [1]
R [R+Rcjoinedbyjumper]
O/B Changeovervalve[5]
Y Compressor relay
G Fan relay
C 24V common [3]
K OptionalTHP9045WiringModule
Terminal [9]
S1/S2 Optional remote sensor
2H/1C Heat Pump (with auxiliary heat)
L Equipmentmonitor[6,7]
Aux/E Auxiliaryheatrelay(Heat2)[8]
Rc Power [1]
R [R+Rcjoinedbyjumper]
O/B Changeovervalve[5]
Y Compressor relay
G Fan relay
C 24V common [3]
K OptionalTHP9045WiringModule
Terminal [9]
S1/S2 Optional remote sensor
2H/2C Heat Pump (no auxiliary heat)
Y2 Compressor 2 relay
Rc Power [1]
R [R+Rcjoinedbyjumper]
O/B Changeovervalve[5]
Y Compressor 1 relay
G Fan relay
C 24V common [3]
K OptionalTHP9045WiringModule
Terminal [9]
S1/S2 Optional remote sensor
3H/2C Heat Pump (with auxiliary heat)
Y2 Compressor 2 relay
L EquipmentMonitor[6,7]
Aux/E Auxillaryheatrelay(Heat2)[8]
Rc Power
R [R+Rcjoinedbyjumper]
O/B Changeovervalue[5]
Y Compressor 1 relay
G Fan relay
S1/S2 Optional remote sensor
C 24V common [3]
K OptionalTHP9045WiringModule
Terminal [9]