Enable/ Disable Switch; Power Supply Test - State Water Heaters SUF 119300 Service Handbook

5. Connect the ground wire from the power supply to the grounding lug inside the junction box. See
Junction Box Assembly Figure below and "Wiring Diagram" on Page 50.
6. Replace junction box cover when connections are complete.
Note: Do not apply power to the water heater before installation is complete and the water heater is filled
with water.
Heater Wiring
(Factory Installed)
Ground

ENABLE/ DISABLE SWITCH

The Enable/Disable Switch is NOT an "on/off" switch and does not disconnect 120 volt power to the CCB and
other heater components. When in the "Disabled" position the switch removes electrical power from the Gas
Control Valve so that water heating is disabled. The display, CCB, and other electrical components will still
be energized and the display will read "Water Heating Disabled". The Enable/Disable Switch can be used to
disable operation and reset error codes. To operate the water heater, make sure the switch is set to "Enabled"
position. Turn power off at the source (circuit breaker) during installation and servicing.

POWER SUPPLY TEST

Proper grounding and polarity can be verified with an AC volt meter by taking three voltage readings at the
power supply wiring inside the water heater's 120 VAC junction box.
Check for AC voltage between:
1. Hot & Neutral - should be approximately 120 VAC.
2. Hot & Ground - should be approximately 120 VAC.
3. Neutral & Ground - should be approximately 0 VAC.
Junction Box Assembly
Enable/ Disable Switch
Servicing should only be performed by a Qualified Service Technician
Ground Terminal
Lead Wire
L1 (Black Wire)
Neutral (White Wire)
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