Option A Wiring; Option B Wiring - Xylem McDonnell & Miller PSE-800-M Low Water Cut-off Application, Installation, Operation, And Maintenance Manual

Installation

Option A wiring

Voltage of the new manual reset LWCO is the same as the existing auto reset LWCO
1. Remove existing wire from terminal B of existing Auto Reset LWCO and connect to
terminal B of new Manual Reset LWCO.
2. Connect new wire from terminal B of existing Auto Reset LWCO to terminal H of new
Manual Reset LWCO.
3. Connect new wire from terminal N of existing Auto Reset LWCO to terminal N of new
Manual Reset LWCO.
1. Factory jumper bar
_ _ _ _ Dashed lines indicate existing wires.
_____ Solid lines indicate new wires.
Water feeder should be wired to existing Auto Reset LWCO. Wiring diagrams for the water
feeder can be found in the water feeder installation instruction manual.

Option B wiring

Wiring a new 120 V manual reset LWCO to a boiler. Burner circuit voltage could be 24 V or
120 V. Existing LWCO could be either probe or float type.
1. Remove the existing hot "H" wire from the service switch and the L1 connection on the
boiler.
2. Connect a new hot "H" wire from the service switch to terminal H on the LWCO.
3. Connect a new hot "H" wire from terminal "B" on the LWCO to the L1 connection on
the boiler.
4. Connect a new wire to terminal "N" of the LWCO and splice it to the existing neutral
"N" wire.
10
2
3
1
Existing wiring to boiler
N H C W B
1
PSE-800-M Low Water Cut-off Installation, Operation, and Maintenance Manual
New wiring to boiler
N H C W B
1
N H C W B
1