White Rodgers 1F86-0244 User Manual

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WIRING DIAGRAMS 
R
C
24 VAC
120 VAC
Hot
Neutral
THERMOSTAT
SYSTEM
G
W
Figure 2. Typical wiring diagram for single transformer single stage systems
TRANSFORMER
(Class II Current Limited)
Changeover
Relay*
Y
O/B
Compressor
Contactor
* Changeover Relay is energized in COOL when O/B switch is in the “O” position
Changeover Relay is energized in HEAT when O/B switch is in the “B” position
Heat Relay
Fan
Relay
Optional
Optional Jumper for 
Single Stage Heat Pump
R
C
24 VAC
120 VAC
Hot
Neutral
THERMOSTAT
SYSTEM
G
W
Figure 3. Typical wiring diagram for two transformer single stage systems with NO safety circuits
TRANSFORMER
(Class II Current Limited)
Changeover
Relay*
Y
O/B
Compressor
Contactor
* Changeover Relay is energized in COOL when O/B switch is in the “O” position
Changeover Relay is energized in HEAT when O/B switch is in the “B” position
Heat Relay
Fan
Relay
Optional
Limit or
Safety
Switches
TWO COMMONS MUST
BE JUMPERED TOGETHER!
HOT
NEUTRAL
120 VAC
24 VAC
CUT AND
TAPE OFF!
If  safety  circuits  are  in 
only one of the systems, 
remove  the  transformer 
of  the  system  with 
NO 
safety circuits.
NOTE
Optional Jumper for 
Single Stage Heat Pump
R
C
G
W
Figure 4. Typical wiring diagram for two transformer single stage systems with safety circuits in BOTH systems
Changeover
Relay*
Y
O/B
Compressor
Contactor
* Changeover Relay is energized in COOL when O/B switch is in the “O” position
Changeover Relay is energized in HEAT when O/B switch is in the “B” position
Heat
Relay
Fan
Relay
Optional
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
Optional Jumper for 
Single Stage Heat Pump