The problem with answering questions where somebody cannot program a timer, or programming stopped working, is that expert doesn't know if timer is defective, or needs to be reset, or timer has conflicting programming, or if person has mis-read the instruction manual, or if wrong button sequence is being used, or if internal battery has gone bad, or if circuit has interference or loose wiring, or if light bulb burned out, and however expert guesses, the person asking question is unhappy because the timer still doesn't work and/or the manual still doesn't make sense.
I work with timers every day and suggest the following steps to get started:
Reset timer and try setting program again.
Write out steps in manual at point where timer doesn't seem to work.
Double-check that you are pushing correct buttons all the way down.
Make sure same days of operation are selected for ON and for OFF. For example if ON is set for all days, and OFF is set for Tuesday, then timer will not work as expected.
Reset timer and make sure there are no conflicting or overlapping programs, or timer will not work as expected.
Test outlet with cheap circuit analyzer from home center, try timer on different outlet, try timer on different Load, check that Load works when plugged into outlet without the timer.
Save some headaches listed above, and buy another 15089 at Home Depot and return defective one in new package.http://waterheatertimer.org/GE-timers-and-manuals.html#15079http://waterheatertimer.org/Woods-timers-and-manuals.html#troubleshoot
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