Wiring diagrams, Heat pump terminal outputs – White Rodgers 1F85-277 User Manual
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WIRING DIAGRAMS
WIRING DIAGRAMS
WIRING DIAGRAMS
WIRING DIAGRAMS
WIRING DIAGRAMS
Refer to equipment manufacturers' instructions for specific
system wiring information.
You can configure the thermostat for use with the following
heat pump system types:
HEAT PUMP TYPE 1. Single stage compressor system; gas
or electric backup.
This thermostat is designed to operate a single-transformer
system. If you have a two-transformer system, cut and tape off
Heat Pump Terminal Outputs
Heat Pump Terminal Outputs
Heat Pump Terminal Outputs
Heat Pump Terminal Outputs
Heat Pump Terminal Outputs
one transformer. If transformer safety circuits are in only one of
the systems, remove the transformer of the system with NO
safety circuits. If required, replace remaining transformer with
a 75VA Class II transformer. After disconnecting one trans-
former, the two commons must be jumpered together.
Use the terminal output information below to help you wire the
thermostat properly for your heat pump system. After wiring, see
CONFIGURATION section for proper thermostat configuration.
SYSTEM
SYSTEM
SYSTEM
SYSTEM
SYSTEM
L
L
L
L
L
C*
C*
C*
C*
C*
R
R
R
R
R
W2
W2
W2
W2
W2
E/W1
E/W1
E/W1
E/W1
E/W1
Y2
Y2
Y2
Y2
Y2
Y1
Y1
Y1
Y1
Y1
G
G
G
G
G
O
O
O
O
O
B
B
B
B
B
Heat
Malfunction
24 Volt
24 Volt HP 1 and Emergency
No
Heat and
Blower/Fan Energized Energized Energized
Pump 1
Light
(Common) (Hot) Emergency
Mode
Output
Cool mode
on call for Heat
in Cool
in Heat
2nd stage
1st stage
1st stage
and Cool
Mode
OFF
Heat
HP 2
2nd
(compressor) Set GAS/ELEC switch
Emergency
Pump 2
3rd stage
stage
for Emergency mode
mode
compressor
THERMOSTAT TERMINALS (HEAT PUMP)
THERMOSTAT TERMINALS (HEAT PUMP)
THERMOSTAT TERMINALS (HEAT PUMP)
THERMOSTAT TERMINALS (HEAT PUMP)
THERMOSTAT TERMINALS (HEAT PUMP)
L
R
E/W1
SYSTEM
MONITOR
SWITCH
G
W2
2nd Stage
Compressor
C
Y1
Y2
Compressor
Contactor
Aux
Heat
Relay
Fan
Relay
Emergency
Heat
Relay
TWO COMMONS MUST
BE JUMPERED TOGETHER!
24 VAC
120 VAC
HOT
NEUTRAL
THERMOSTAT
SYSTEM
HOT
NEUTRAL
120 VAC
Limit or
Safety
Switches
Limit or
Safety
Switches
Limit or
Safety
Switches
24 VAC
Limit or
Safety
Switches
COMMON
COMMON
Auxiliary
Heating
Transformer
(Class II
Current Limited)
Heat Pump Transformer
(Class II Current Limited)
24 VAC
ACCESSORY
RELAY N.O.
CONTACT
Polarity must be observed. If the HOT side of the second transformer
is jumpered to the COMMON side of the first transformer a short will
be made. Damage to equipment will occur when power is restored.
NOTE
The accessory relay scheme
is required when safety
circuits exist in both systems.
NOTE
Reversing
Valve
Energized in
Heat, Off,
Emergency
Mode
B
Reversing
Valve
Energized in
Cool Mode
O
*
Figure 4. Typical wiring diagram for two transformer heat pump systems with safety circuits in BOTH systems
*The 24 volt neutral connection to terminal C on the thermostat is not required if you replace the batteries once a year with fresh “AA” Energizer
®
alkaline batteries.
C
R
Y2
Compressor
Contactor
Stage 1
Heat
Relay
Stage 1
Heat
Relay
Stage 2
24 VAC
120 VAC
Hot
Neutral
THERMOSTAT
SYSTEM
Y1
E/W1
W2
Figure 5. Typical wiring diagram for single transformer multi-stage systems
Fan
Relay
G
TRANSFORMER
(Class II, Current Limited)
Compressor
Contactor
Stage 2
Reversing
Valve
Energized in
Heat Mode
Off Emergency
B
Reversing
Valve
Energized in
Cool Mode
O
*
*The 24 volt neutral connection to terminal C on the thermostat is not required if you replace the batteries once a year with fresh “AA” Energizer
®
alkaline batteries.
*The 24 volt neutral connection to terminal C on the thermostat is not required if you replace the batteries once a year with fresh “AA” Energizer
®
alkaline batteries.