publication

149 / 221

Single
Stage 1
(SS1)
Multi-
Stage 2
(MS2)
O
Energized Constantly
in
Cool Mode
B
Energized Constantly
in Heat, Off,
Emergency
Mode
No
Output
Cool
Mode
2nd
Stage
Cool Mode
1st Stage
Blower/
Circulator
Fan Energized
on Call for
Cool (and
Heat if
configured
for Electric
Heat)
No Output
Heat Mode
2nd Stage
Heat
Mode
1st Stage
Optional*
24 Volt
(Com-
mon)
24 Volt
(Hot)
Cool
System
Y G W/E C L RC
CLASS II
TRANSFORMER
HOT
24VAC
NEUTRAL
120VAC
24 Volt
(Hot)
Heat
RH Y2 W2
Jumper
Fault
Indicator
or
System
Malfunction
Switch
Comfort Alert II Module
or Similar System
Malfunction Module
O/B
* Common connection
required for fault or
malfunction indication.
TYPICAL WIRING 1F83-0422/1F85-0422
Single Stage or Multi-Stage System (No Heat Pump)
with Two Transformers
Single
Stage 1
(SS1)
Multi-
Stage 2
(MS2)
O
Energized
Constantly
in
Cool Mode
B
Energized
Constantly
in Heat, Off,
Emergency
Mode
No
Output
Cool
Mode
2nd
Stage
Cool Mode
1st Stage
Blower/
Circulator
Fan Energized
on Call for
Cool (and
Heat if
configured
for Electric
Heat)
No Output
Heat Mode
2nd Stage
Heat
Mode
1st Stage
Optional
24 Volt
(Com-
mon)
Fault
Indicator
(NOT
USED)
24 Volt
(Hot)
Cool
System
Y G W/E C L RC
CLASS II
TRANSFORMER
HOT
24VAC
NEUTRAL
120VAC
24 Volt
(Hot)
Heat
RH
120VAC
Remove Jumper Wire
between RH & RC
HOT
24VAC
NEUTRAL
CLASS II
TRANSFORMER
HEATING
COOLING
Y2 W2
Jumper
O/B
Single Stage
3-wire
Zone Valve
application
Blower/Circulator
Fan Energized
Opens
Valve
(4)
Constant
24 Volt
(Com-
mon)
24 Volt
(Hot)
Cool
System
6 Y W C RC
CLASS II
TRANSFORMER
HOT
24VAC
NEUTRAL
120VAC
24 Volt
(Hot)
Heat
(5)
RH G
Jumper
Closes
Valve
(6)
NOTE: If continuous backlight or hardwired power input are desired but do not function in both
HEAT and COOL modes, cut the heating transformer 24V wires and tape off. Connect the neutral
circuit disconnected from the heating transformer to the neutral circuit of the cooling transformer.
Disconnect the wire to the RH terminal and install a jumper between RH and RC. Depending on the
system requirements, replace the cooling transformer with a 75VA class II transformer if needed.
3-Wire (SPDT) Heat Only Zone Valve Wiring
Single Stage or Multi-Stage System (No Heat Pump) with Single Transformer
150
TECHNICAL HELP