Raypak VERSA 155C Operating And Installation Instructions page 18

For 120 V input power to the unit, connect the black wire
WIRING DIAGRAM KEY
to the "L1" or hot leg of the power supply. Connect the
white wire to the "L2" or neutral leg of the power supply.
Attach the wire nut to the red wire. There should be no
connection to the red wire for 120V operation.
Fig. #9240
For 240 V input power to the unit, connect the black wire
to the "L1" or hot leg of the power supply. Connect the red
wire to the "L2" or second hot leg of the power supply.
Attach the wire nut to the white wire. There should be no
connection to the white wire for 240V operation.
Fig. # 8096.0
Fig. # 9241
Heater must be electrically grounded and bonded in
accordance with local codes, or, in the absence of local
codes, with the latest edition of the National Electrical code,
ANSI/NFPA 70.
NOTE: Input power to the heater (120/240V) should be
supplied from the load (Pump) side of time clock or switch.
Connecting heater to continuous power source will allow
"Fail" indications (service and pressure switch) when pump
is not operating.
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