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25
PC702 2–Stage Boiler Reset Control Connected to 2 EXP Switching Relays
FOUR ZONE SWITCHING RELAY
WITH OPTIONAL PRIORITY
ZONE 4
ON
OFF
PRIORITY
120V RELAY
FUSE 1 AMP
24 VAC
POWER
MASTER
PLUG-IN CARDS
RESET NORMAL
SLAVE
POWER
CONTROL
INTERFACE
THERMOSTATS
ZONE 1 ZONE 2 ZONE 3 ZONE 4
120 VAC INPUT
120 VOLT CIRCULATORS
ZC ZR
X X
END
SWITCH
ZONE1 ZONE2 ZONE3 ZONE4 POWER
INPUT
ZONE 2
POWER
ZONE 1
ZONE 3
ZONE 4
JUMPER
SWITCH SETTINGS
Master/Slave: Master
Reset/Normal: Normal
Priority Zone: On or Off
12 34
EXPANSION
ZONE
CONTROL
BOIL
SEN
OUT
SEN
BOILER SENSOR
OUTDOOR
SENSOR
PC702
STAGE
1
STAGE
2
BOILER
#2
BOILER
#1
DHW
DEMAND
SR 504-EXP
WIRING NEEDED ONLY IF
PRIORITY ZONE IS DHW
MASTER
FOUR ZONE SWITCHING RELAY
WITH OPTIONAL PRIORITY
ZONE 4
ON
OFF
PRIORITY
120V RELAY
FUSE 1 AMP
24 VAC
POWER
MASTER
PLUG-IN CARDS
RESET NORMAL
SLAVE
POWER
CONTROL
INTERFACE
THERMOSTATS
ZONE 1 ZONE 2 ZONE 3 ZONE 4
120 VAC INPUT
120 VOLT CIRCULATORS
ZC ZR
X X
END
SWITCH
ZONE1 ZONE2 ZONE3 ZONE4 POWER
INPUT
ZONE 2
POWER
ZONE 1
ZONE 3
ZONE 4
JUMPER
H
N
SWITCH SETTINGS
Master/Slave: Slave
Reset/Normal: Normal
Priority Zone: No Priority
12 34
EXPANSION
SR 504-EXP
SLAVE
SYSTEM
CIRCULATOR
(OPTIONAL)
T
T