(cont.)
NOTE: Tankless coil has priority.
THREE ZONE SWITCHING RELAY
WITH OPTIONAL PRIORITY
THERMOSTAT
FUSE 1 AMP
24 VAC
POWER
ZONE 1 ZONE 2
ZONE 3
120 VOLT CIRCULATORS
ZC
X1
ZONE1 ZONE2
ZONE3
SR 503
ZONE 2
POWER
ZONE 1
ZONE 3
L1
L2
T
T
LINE VOLTAGE
OIL BURNER RELAY
CIRCULATOR
ON BOILER
(IF ATTACHED)
B2
C1
B1
ZR
HONEYWELL L8124
OR EQUAL
120 VAC INPUT
C2
ZC
THERMOSTAT
L1
L2
(NEUTRAL)
(HOT)
CIRCUIT
BREAKER
CUSTOMER
EMERGENCY
SWITCH
THERMAL
FUSE
(FIROMATIC)
SERVICE
SWITCH
LOW
WATER
CUTOFF
NP
H
X2
ZR
NOTE: The boiler operating control’s ZC terminal will see the load of the circulator(s).
FOUR ZONE SWITCHING RELAY
WITH OPTIONAL PRIORITY
THERMOSTATS
ZONE 4
ON
OFF
PRIORITY
120V RELAY
FUSE 1 AMP
24 VAC
POWER
ZONE 1 ZONE 2 ZONE 3 ZONE 4
120 VOLT CIRCULATORS
ZC ZR
X X
END
SWITCH
ZONE1 ZONE2 ZONE3 ZONE4 POWER
INPUT
SR 504
ZONE 2
POWER
ZONE 1
ZONE 3
ZONE 4
L1
L2
T
T
LINE VOLTAGE
OIL BURNER RELAY
CIRCULATOR
ON BOILER
(IF ATTACHED)
B2
C1
B1
ZR
HONEYWELL L8124
OR EQUAL
120 VAC INPUT
C2
ZC
THERMOSTAT
L1
L2
(NEUTRAL)
(HOT)
CIRCUIT
BREAKER
CUSTOMER
EMERGENCY
SWITCH
THERMAL
FUSE
(FIROMATIC)
SERVICE
SWITCH
LOW
WATER
CUTOFF
4