Specifications

6 7
WIRING TERMINAL
Wire specifications
18-24 gauge thermostat wire
Installation notes
• Ensure power at the HVAC equipment is off.
• Loosen screw terminals, insert stripped wire and
re-tighten.
• Push the excess wire back into the opening and plug
the wall opening to prevent drafts.
INSTALLATION
RC – 24 VAC supply cooling*
R – 24 VAC supply heating*
W – 1st stage heat / auxiliary
Y – 1st stage cooling / compressor
G – Fan
C – Common (optional when powered by batteries)
S1 & S2 – outdoor temperature sensor (optional)
O/B – Reversing valve
L – System fault indicator
W2 – 2nd stage heat / auxiliary
Y2 – 2nd stage cooling / compressor
* Jumper between RC & R is used in single transformer systems
(see wiring diagrams).
C
G
Y
W
R
L
S1
S2
O/B
W2
Y2
RC
WIRING – SINGLE TRANSFORMER (USE
JUMPER WIRE) FOR HEAT/COOL SYSTEM
INSTALLATION
1st HEATING
1st COOLING
FAN
2nd HEATING
2nd COOLING
OUTDOOR TEMP
SENSOR
NOT USED NOT USED
JUMPER
TRANSFORMER
C
G
Y
W
R
L
S1
S2
O/B
W2
Y2
RC
WIRING – TWO TRANSFORMERS (REMOVE
JUMPER WIRE) FOR HEAT/COOL SYSTEM
1st HEATING
1st COOLING
FAN
2nd HEATING
2nd COOLING
OUTDOOR TEMP
SENSOR
NOT USED NOT USED
HEATING
TRANSFORMER
COOLING
TRANSFORMER
C
G
Y
W
R
L
S1
S2
O/B
W2
Y2
RC