Question about Electric Intermatic Wh 21 Water Heater Timer

1 Answer

There is a light on the outside of timer should it stay on all the time

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1 Answer

1) WH21 manual does not say if indicator lights up when Load is ON. That says indicator lights up when timer has power.
2) Flip manual control to reverse program and see if light stays on or goes off.

3) GE15207 water-heater-timer has two different indicator lights. One is ON when timer has power. The other is ON when Load has power. But GE timer has NO and NC terminals.

4) The reason I answered this question is that folks have problems wiring timers and then ask questions trying to piece together why timer is not working.
5) If timer is not functioning as expected, read below, or add a comment with details about your wiring.

6) Wiring WH21
240V circuits have 2 hot leads.
Hot leads from breaker connect to center terminal and to left terminal.
Leads going to Load (water heater) connect to center terminal and to right terminal
If you have leads from breaker and leads to Load reversed, timer will not function except when manual control is switched ON.
In this case, reverse wires on right and left terminals.

Posted on Dec 03, 2010


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