OPERATION & SERVICE
Temperature Sensor Resistance Test
1Secure power to the water heater at the main breaker or disconnect switch.
2Unplug the J5 plug from the CCB circuit board - see page 42 for location.
3Using an ohm meter: set the ohm meter range to a scale above 30,000 ohms initially.
4Touch the ohm meter probes between the two middle pins (black wires) of the J5 plug end as shown in the image below. Compare the measured resistance value (ohms) to the values given in the resistance data table below. Temperature probes are very reliable and should only be replaced when:
•The resistance test indicates an “open” (infinite resistance) or a “direct short” (no resistance) circuit.
•The nature of the service problem is temperature control and the resistance readings are considerably (25% or more) different than the values in the table here at the given temperature.
Checking Temperature Sensor Resistance
Temperature Sensor Resistance Data
WATER TEMPERATURE | RESISTANCE | |
Celsius | Fahrenheit | IN OHMS |
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3° | 40° | 26,435 |
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21° | 70° | 11,974 |
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38° | 100° | 5,862 |
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49° | 120° | 3,780 |
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55° | 130° | 3,066 |
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60° | 140° | 2,503 |
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71° | 160° | 1,698 |
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82° | 180° | 1,177 |
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Servicing should only be performed by a Qualified Service Agent
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