Installation guide

VisionPRO
®
TH8110 / TH8320 / TH8321
5
Wiring
Wiring guide — heat pump systems
2H/2C Heat Pump (no auxiliary heat)
Y2 Compressor 2 relay
Rc Power [1]
R [R+Rc joined by jumper]
O/B Changeover valve [5]
Y Compressor 1 relay
G Fan relay
C 24VAC common [3]
S1 Optional outdoor/remote sensor
S2 Optional outdoor/remote sensor
3H/2C Heat Pump (with auxiliary heat)
Y2 Compressor 2 relay
L Equipment monitor [6, 7]
E Emergency heat relay [8]
Aux Auxiliary heat relay (Heat 2) [8]
Rc Power [1]
R [R+Rc joined by jumper]
O/B Changeover valve [5]
Y Compressor 1 relay
G Fan relay
C 24VAC common [3]
S1 Optional outdoor/remote sensor
S2 Optional outdoor/remote sensor
See [notes] below
[1] Power supply. Provide disconnect means and overload protection as required.
[3] Optional 24VAC common connection.
[5] O/B set to control as either O or B in installer setup.
[6] If L terminal is used, 24VAC common (terminal C) must
be connected.
[7] Heat pump reset (powered continuously when thermostat is set to Em. Heat;
system monitor when set to Heat, Cool or Off).
[8] Install field jumper between Aux and E terminals if there is no emergency heat relay.
Shaded areas below apply only to TH8320/TH8321
1H/1C Heat Pump (no auxiliary heat)
Rc Power [1]
R [R+Rc joined by jumper]
O/B Changeover valve [5]
Y Compressor relay
G Fan relay
C 24VAC common [3]
S1 Optional outdoor/remote sensor
S2 Optional outdoor/remote sensor
2H/1C Heat Pump (with auxiliary heat)
L Equipment monitor [6, 7]
E Emergency heat relay [8]
Aux Auxiliary heat relay (Heat 2) [8]
Rc Power [1]
R [R+Rc joined by jumper]
O/B Changeover valve [5]
Y Compressor relay
G Fan relay
C 24VAC common [3]
S1 Optional outdoor/remote sensor
S2 Optional outdoor/remote sensor