16
BOILER
120 V
AC INPUT
TO: "TT" ON BOILER
H
N
A
SR 502
ZONE1
ZONE2
ZONE3
24 V
A
C
POWER
FUSE 1 AMP
ZONE1
ZONE2
ZONE3
JUMPERS
N P ZC H X ZR
1
X
2
ZONE 2
POWER
ZONE 1
TWO ZONE SWITCHING RELAY
WITH OPTIONAL PRIORITY
A
PRIORITY
OFF
12
34
EXPANSION
FOUR ZONE SWITCHING RELAY
WITH OPTIONAL PRIORITY
ZONE 4
ON
OFF
PRIORITY
120V RELA
Y
FUSE 1 AMP
24 V
A
C
POWER
MASTER
PLUG-IN CARDS
RESET NORMAL
SLA
VE
POWER
CONTROL
INTERF
ACE
ZONE 1
Z
ONE 2
Z
ONE 3
ZONE 4
120 VOL
T CIRCULA
TORS
ZC ZR
X X
END
SWITCH
ZONE1
ZONE2
ZONE3
ZONE4
POWER
INPUT
SR 504-EXP
ZONE 2
POWER
ZONE 1
ZONE 3
ZONE 4
JUMPER
SWITCH SETTINGS
Master/Slave: Master
Reset/Normal: Normal
Priority Zone: On
12
34
EXPANSION
SR504-EXP
T
FOUR ZONE SWITCHING RELAY
WITH OPTIONAL PRIORITY
ZONE 4
ON
OFF
PRIORITY
120V RELA
Y
FUSE 1 AMP
24 V
A
C
POWER
MASTER
PLUG-IN CARDS
RESET NORMAL
SLA
VE
POWER
CONTROL
INTERF
ACE
ZONE 1
Z
ONE 2
Z
ONE 3
ZONE 4
120 VOL
T CIRCULA
TORS
ZC ZR
X X
END
SWITCH
ZONE1
ZONE2
ZONE3
ZONE4
POWER
INPUT
SR 504-EXP
ZONE 2
POWER
ZONE 1
ZONE 3
ZONE 4
JUMPER
SWITCH SETTINGS
Master/Slave: Slave
Reset/Normal: Normal
Priority Zone: Off
SR504-EXP
T
DHW
CIRCULATORS
AQUASTATS ON
DHW HEATERS
MASTER
SLAVE
ZONE
NOT
USED
2 Indir
ect W
ater Heater
s with P
rior
it
y Connected to E
XP Switc
hing R
elays
