<!-- from fixya rte -->Water indicator light stays on - Coffee Makers & Espresso Machines

After replacing the Water Panel, turn the control knob to the “Test/Reset” position until the “Change Water Panel” light blinks to reset the Water Panel change indicator timer.

It would stay on if the sensor is unplugged. That indicates a malfunction. Why would you unplug it? Have you drained your water separator? You would probably want to measure resistance on the sensor itself, to see if it is malfunctioning. Water in diesel is not a good thing. If you are sure the indicator light is telling you there is water when there is not, you may have a bad sensor or a short in the wire, etc. The reference voltage for most computer controlled sensors is 5V. I do not see what type of vehicle this is or what year, so my information is very limited. You do not want that sensor to stay unplugged though. ESPECIALLY IF IT IS A NEWER VEHICLE (96 & later). If the sensor is bad, replace it.

I’m happy to assist further over the phone at https://www.6ya.com/expert/kim_3202917d7c587455

Kenmore is AO Smith product
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Check wireing

In the water bucket is a float assm. scale forms on the assm. and causes it to stick. Remove the float assm. and carefully remove the scale. Should start working again once done. If not you may have to replace it.

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.

Water Filter Status Indicator
Light (select models)
The Water Filter Status Indicator Light serves as a
reminder to replace the water filter. A green light
indicates that the filter is in good condition. A red light
indicates the filter should be changed. Once light turns
red, it will remain red until function is reset.
To Reset Indicator:
• Press and hold both the Lock and Water
buttons simultaneously for four seconds. The
green filter status indicator light will flash
three times when the function has
successfully reset.

I installed a tankless heater in my home, I had the same problem, I discovered that the unit was not adequate for the water flow that I needed, I went up to a bigger unit and solved my problems, check to see what the flow rate is recommened for yours

That light in the switch should only be on momentarily while it is igniting, and then go out when everything is ok. If light stays on, it's to alert you that for some reason, the burner did not ignite, such as propane is off, or some other reason it didn't ignite. If the light stay out, then the burner should be working properly.

Afer you change the filter and have run the water for about 1 minute you then hold down the light & lock button together and this should turn the change filter light off.