9
WIRING DIAGRAMS
For Motorized Valves, refer to the valve manufacturer's wiring instructions.
Pump Control Only
1. Install a starter or relay in pump control circuit,
as shown, to prevent damage to snap switch
and help insure proper switch/control operation.
Failure to do so may shorten the life of the switch
when actual amperage exceeds switch rating.
2. Connect wires from holding coil of pump starter
or relay to terminals 1 and 2 as shown.
1. Main Line Switch - For burner circuits within
the switch’s electrical rating.
2. Pilot Switch - To holding coil of a starter when
the burner circuit exceeds the switch’s electrical
rating.
1 2
4 5 6
ALARM
NEUTRAL
HOT
ALARM
NEUTRAL
HOT
1 2
4 5 6
1 2
4 5 6
SEE PUMP
CONTROL
CIRCUIT
TO NEUTRAL
TO BURNER CONTROL CIRCUIT
HOT
ALARM
1 2
4 5 6
LOAD
LINE (3 PHASE)
SEE PUMP
CONTROL
CIRCUIT
ALARM
1 2
4 5 6
LOAD
LINE
OR
OR
Combination Pump Control, Low Water Cut-Off and Alarm
Alarm Circuit Only
1. Low Water Alarm
2. High Water Alarm
NOTE
To help insure most effective operation,
balance boiler feed pump(s) to deliver
required water feed rate to match boiler
steaming requirements.
NOTE
For Model 159S, use terminals 5 and 6 from
starter or relay for pump #2.
Low Water Cut-Off Only
1. Main Line Switch - For burner circuits within the
switch’s electrical rating.
LINE
LOAD
1 2
4 5 6
1 2
4 5 6
LOAD
LINE
OR
2. Pilot Switch - To holding coil of a starter when
the burner circuit exceeds the switch’s electrical
rating.
