American Water Heater STCE3-52/80/119 ユーザーズマニュアル

Servicing should only be performed by a Qualified Service Agent

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A thorough visual inspection of the contactors used on Electronic Control Models should be 
performed as part of any regular maintenance program and whenever the water heater is 
being serviced. Refer to the listed Steps and images below for this procedure.

1

Secure power to the water heater at the main breaker or disconnect switch.

2

Verify with an AC volt meter that there is not any voltage present at the Power Distribution Block, power 
circuit fuse block and all wiring terminals on the contactors. See Figure 2 on page 9 for the location of 
these components.

3

Remove the top cover (two small screws) from the contactor. 

4

Check for and remove any debris from the area surrounding the switch contacts. IE: ants will occasionally 
infest the switch contacts and eventually cause the contactor to malfunction.

5

Physically test the mechanical spring action of the contactor by depressing the contactor mechanism. If the 
action is not smooth and/or sticks - replace the contactor.

6

Perform a close visual inspection of the switch contacts. The contacts are silver plated and should be 
smooth. Contactor chatter (see pages 6 & 34), voltage spikes, arcing, excessive current along with normal 
wear and tear can cause the normally smooth surface of the contacts to become burnt, pitted and 
damaged. In extreme cases the contacts can “weld” closed. The switch contacts are not replaceable. If the 
contacts show signs of excessive wear - replace the contactor.

7

Replace the top cover on all contactors when inspection is complete.