PRE SERVICE CHECKS
PRE SERVICE CHECKS
WIRING CONNECTIONS
With the power supply to the water heater turned off ensure the wiring connections are properly tightened to all components including: high voltage terminal blocks, fuse blocks, contactors, transformers and heating elements.
Loose connections at any connection point will cause increased amperage and excessive heat which can damage wiring and components. Whenever worn or damaged wiring and components must be replaced ensure all wiring connections are properly tightened before putting the water heater back in service.
SERVICE PRECAUTIONS
1DO NOT energize the branch circuit supplying power to the water heater or test the water heater electrical system before the water heater is completely filled with water. Read the start up procedures in the Instruction Manual that came with the water heater.
2Be sure to turn off power and use a lock out device at the branch circuit power supply disconnect switch or breaker when servicing the electrical system of the water heater. Never touch electrical components with wet hands or when standing in water.
3When replacing heating elements ensure they are rated at the correct voltage and KW for the water heater being serviced - see Heating Element Ratings and Heating Element Configurations on page 21 and Replacing Heating Elements on page 26.
4When replacing fuses use an insulated fuse puller to remove and install fuses. Always use the correct size for the circuit. See the Replacement Fuses Service Note on page 17 in this manual.
5Using an AC volt meter measure the branch circuit power supply voltage to the water heater. Ensure the measured voltage of the branch circuit supplying power to the water heater matches the water heater’s rating label - see pages 12 - 14.
6Ensure the internal power phase configuration matches the power supply to the water heater. The water heaters covered by this manual are phase convertible - see pages 15 and 16.
7Electronic Control Models covered by this manual are equipped with contactors and will have a multi tap control circuit transformer. This is a step down transformer that outputs 120 VAC (secondary winding) which is used to power the electronic control system and energize the contactor coils. The transformer can accommodate different power supply voltages and has multiple input voltage connections or “taps.” Ensure the input supply voltage (primary winding) wiring to the transformer is connected properly. See page 34 in this manual.
Service Note - Contactor Chatter: Incorrect supply voltage wiring to the multiple tap 120 VAC Control Circuit Transformer on Electronic Control Models will cause low/high output voltage from the transformer. This can cause contactors to open and close their contacts rapidly (contactor chatter) and result in permanent damage to the contactors. Ensure the primary winding of the multiple tap 120 VAC Control Circuit Transformer is wired to match the power supply voltage - see pages 12
Servicing should only be performed by a Qualified Service Agent
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