Installation Guide
4
69-2486—07
Wiring
See [notes] below
[1] Power supply. Provide disconnect means and overload protection as required.
[3] Connection to 24VAC common at the transformer is required.
[9] See "Optional THP9045 Wiring Module" on
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 transformers).
W
1st stage heat relay.
W2
2nd stage heat relay
Y
1st stage compressor contactor.
Y2
2nd stage compressor contactor.
G
Fan relay.
K
Optional THP9045 Wiring Module
Terminal [9]
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.
Y
1st stage compressor contactor.
Y2
2nd stage compressor contactor.
Aux
Auxiliary heat relay.
G
Fan relay.
E
Emergency heat relay.
L
Heat pump reset (powered continu-
ously when System is set to Em Heat;
system monitor when set to Heat,
Cool or Off).
O/B
Changeover valve for heat pumps.
K
Optional THP9045 Wiring Module
Terminal [9]
1H/1C System (1 transformer)
Rc
Power [1]
R
[R+Rc joined by jumper]
W
Heat relay
Y
Compressor contactor
G
Fan relay
C
24VAC common [3]
K
Optional THP9045 Wiring Module
Terminal [9]
Heat Only System
Rc
Power [1]
R
[R+Rc joined by jumper]
W
Heat relay
C
24VAC common [3]
Heat Only System (Series 20)
Rc
[R+Rc joined by jumper]
R
Series 20 valve terminal “R” [1]
W
Series 20 valve terminal “B”
Y
Series 20 valve terminal “W”
C
24VAC common [3]
2H/2C System (1 transformer)
Y2
Cool relay 2
W2
Heat relay 2
Rc
Power [1]
R
[R+Rc joined by jumper]
W
Heat relay 1
Y
Cool relay 1
G
Fan relay
C
24VAC common [3]
K
Optional THP9045 Wiring Module
Terminal
[9]
Wiring guide—conventional systems