Service Manual

70
Service Procedure I
Thermostat Circuit Testing
and Replacement
NOTE: This procedure assumes a cool tank.
WARNING
120 volt potential exposure. Use caution making
voltage checks to avoid personal injury.
CAUTION
Use caution to not damage connectors when
making voltage measurements or jumping terminals.
Condition: Water heater not operating.
Display shows error code 32 (Sensor Reading Faulty)
Unplug or disconnect electrical power to the water heater.
Check continuity of wire harness to sensor. Resistance of harness
should be close to 0 ohms. Replace wire harness if high resistance
is measured (over 0.5 ohms). Check wires for intermittent
connections, shorts, frayed insulation. Replace if necessary.
If wire harness is O.K., check resistance
detailed in Appendix A: (pg 72). Replace
sensor if needed.
Turn power ON to water heater. Run water heater through
heating cycle and verify proper operation. Sensor
temperature can be viewed when burner shuts off (see
section on viewing the display in Service Mode).
Condition: Water heater not operating.
Display shows error code 65 (high water temperature, over 200 °F).
WARNING!
DO NOT reset the display from the Hard Lockout condition
without correcting the cause of the overheating condition.
Turn power OFF. Draw water to cool tank below 120 °F.
Check sensor. Sensor is held in place with a clip
fastened to the well (see photo). Check sensor wire
for potential damage or breaks in the wire
insulation. Is the sensor fully inserted into the well?
If sensor clip is damaged replace
clip. Replace sensor if damaged.
Check sensor resistance.
Continued on
next page.
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