3
WIRING DIAGRAMS
Figure 2 – Single Stage or Multi-Stage System
(No Heat Pump) with Single Transformer
Single Stage 1
(SS1)
Multi Stage 2
(MS2)
System
RC
RH
C
Y
Y2
W/E
W2
G
O/B
6
L
CLASS II
TRANSFORMER
HOT
24VAC
NEUTRAL
120VAC
Call for heat
Heat mode-1st
stage
Heat mode-2nd
stage
No output
24 volt
power for
cooling
24 volt
power for
heating
Cool mode-2nd
stage
24 volt
common
(optional
for system
operation,
required
for remote
sensor)
Call for cool
No Output
Cool mode-1st
stage
Blower/Circulator fan
energized on a call
for cool or Fan On
(also energized in
heating if configured
for Electric Heat)
Installer
Configuration
Menu selects
“O” or “B” for
changeover
function. Set
to “O” terminal
energized in Cool
& Off mode. Set
to “B” terminal
energized in
Heat & mergency
mode
Power closed
connection for
SPDT 3-wire
zone valve
Fault or System
Malfunction
Indicator for
Heat Pumps
with “L” terminal
connection.
Original production
1F95-1291’s
do not have this
connection
Figure 3 – Heat Pump Systems
Heat Pump Connections
If you do not have a heat pump system, refer to figures 3 & 4.
Refer to equipment manufacturers’ instructions for specific system
wiring information.
You can configure the thermostat for use with the following heat pump
systems.
Single Stage and Multi-Stage Connections
Refer to equipment manufacturers’ instructions for specific system
wiring information.
This thermostat is designed to operate a single-transformer or two-
transformer system.
You can configure the thermostat for use with the following fossil fuel
systems:
Heat
Pump 1
(HP1)
Heat
Pump 2
(HP2)
System
RC
RH
C
Y
Y2
*W/E
*W2
G
O/B
6
L
CLASS II
TRANSFORMER
HOT
24VAC
NEUTRAL
120VAC
Heat mode-2nd
stage, Emergency
Mode-1st stage
*Note: Dual Fuel
option de-
energizes Heat
mode stage 1
(compressor)
when auxiliary
heat is energized
Heat mode-3rd
stage, Emergency
Mode-1st stage
*Note: Dual Fuel
option de-
energizes Heat
mode stages 1
and 2 (both
compressors)
when auxiliary
heat is energized
Heat mode-4th
stage, Emergency
Mode-2nd stage
*Note: Dual Fuel
option de-
energizes Heat
mode stages 1
and 2 (both
compressors)
when auxiliary
heat is energized
Heat mode-3rd
stage, Emergency
Mode-2nd stage
*Note: Dual Fuel
option de-
energizes Heat
mode stage 1
(compressor)
when auxiliary
heat is energized
24 volt
power for
cooling
24 volt
power for
heating
Heat mode-2nd
stage,
Cool mode-2nd
stage,
(Compressor)
No Output
24 volt
common
(optional
for system
operation,
required
for remote
sensor)
Heat mode-1st
stage,
Cool mode-1st
stage,
(Compressor)
Blower/Circulator fan
energized on a call
for cool or Fan On
(also energized in
heating if configured
for Electric Heat)
Installer
Configuration
Menu selects
“O” or “B” for
changeover
function. Set
to “O” terminal
energized in Cool
& Off mode. Set
to “B” terminal
energized in
Heat & mergency
mode
Power closed
connection for
SPDT 3-wire
zone valve
Fault or System
Malfunction
Indicator for
Heat Pumps
with “L” terminal
connection.
Original production
1F95-1291’s
do not have this
connection
COOLING
CLASS II
TRANSFORMER
HOT
24VAC
NEUTRAL
120VAC
HEATING
120VAC
*Dual fuel option, if selected turns off compressor(s) when Auxiliary stages energize.
SINGLE STAGE (SS 1)
gas, oil or electric.
MULTI-STAGE (MS 2)
gas, oil or electric.
After wiring, see INSTALLER CONFIGURATION section for proper
thermostat configuration.
HEAT PUMP TYPE 1 (HP 1)
.
Single stage compressor system;
gas or electric backup.
HEAT PUMP TYPE 2 (HP 2).
Multi-stage compressor or two
compressor system with gas or electric backup.
After wiring, see INSTALLER CONFIGURATION section for proper
thermostat configuration.
