T104-20, WH21 & WH40


Utilities in many areas of the country offer two electric rates for residential or commercial customers. One rate has the regular daytime electrical rate, the other is the “off-peak” rate. The “off-peak” rate provides customers with “lower-priced” electricity during the nighttime and weekend periods. The Mechanical Water Heater Timers allow the customer to shift electricity use into these “off-peak” time periods in an attempt to save utility costs.

  • Series Overview
  • Model Lineup
  • Specifications
  • Resources

• Convenient external override switch (WH21 and WH40 only)

• Includes ON/OFF trippers

 Water Heater Control for:

  • Residential
  • Commercial
  • Industrial
  • Institutional/Schools
  • Military Facilities
Product Ratings
ModelSwitchClock Supply Volts 60 HzWattsExternal SwitchAmps - per pole

Enclosure: Type 1 steel enclosure

Motor VAC 60 Hz: 208-277

Amps (per pole): 40 (T104-20 & WH40), 25 (WH21)

Switch Type: DPST (T104-20 & WH40), SPST (WH21)

External Switch: No (T104-20), Yes (WH21 & WH40)

Power Input: 3 Watts Maximum

Shipping Weight: 3 lbs. (1.4 kg)

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