Top Element Hot Water Thermostat 052018


Non-simultaneous (Top) Thermostat – Twin Element Models
A device, responsive to temperature, which controls the supply of electrical energy to the top element to maintain the stored water at the required temperature. It also switches the neutral supply between the top and bottom elements to ensure only one element can be operational at any time. This is known as non-simultaneous operation.



Suitable for most twin element electric hot water systems

Top Thermostat – Non-Simultaneouspage31image3565766720 page31image3565767008

Personal Protective Equipment should be worn when conducting step 2 of this procedure to reduce the risk of electric shock.

  1. Isolate the power supply to the water heater and remove upper and lower front covers.
  2. Confirm with multi-meter between each Active and Neutral at the terminal blockthat voltage is not present.
  3. Remove the protective cover and disconnect wiring from the thermostat (Note wiring positions).
  4. Slide thermostat vertically out of clamp.
  5. Remove any scale or corrosion from cylinder surface.
  6. Slide replacement thermostat into place behind clamp and connect wiring to appropriate points (refer to “Wiring Diagrams” section on page 10). Note: Ensure thermostat face is in good contact with cylinder surface.
  7. Check water heater internal wiring insulation for cracking.
  8. Refit the thermostat protective cover and upper access cover securely.
  9. Conduct an electrical insulation test on the water heater (refer to “Electrical Insulation Testing” on page 28).

10.Replace lower access cover and restore the power supply to the water heater.