Osmolator pump is not turning on when it should.


New member
I have a new osmolator that has been working fine for two weeks, then suddenly it seems to have stopped sensing low water.

Awoke this AM to find the water line 3" bellow the optic sensor --incorrectly reading water as "level". I turned the system off and on again and it filled water for just a couple seconds, then stopped again. The water still below level, yet it read green "level".

I had to turn the pump on and off again about 15 times to get it filled back up to the actual level of the optic sensor. Note: it is running for about 5 seconds....not timing out due to excessive run time.

defective i assume? I have had osmolators before running for several years without any problem. Not sure why this is happening with this one.

When turning it on and off, it correctly turns yellow and says "water below level" it just stops filling too soon and reads it as level.


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Try this, remove the sensor and soak it in vinegar, if you dosed anything near the sensor, , a film of calcium or minerals could form in this short time and basically blind the sensor, generally this takes months, but is not impossible when dosing near the sensor or if a precipitation has occured. It will need to soak for a couple hours and should be shiny when dry, if it has a haze when dry, that is the culprit and more cleaning may be needed.

The brief time the pump is running is part of its program to prime and test the pump and not related to the sensor, it would still do this if the sensor was gone altogether, in this case the yellow just means the pump is on, their is not really a status for dry, just pump on.

While you have the sensor out and dry, plug in the controller, it will flash four lights and beep, it will briefly show one light before starting normal operation, that light is the optic sensor status. Green means it passes, yellow it is generally dirty and this can be as simple as fingerprints, it can also be due to algae, dust and any film, red means it failed, this can be due to being heavily soiled or a break in the wire or a short in the sensor. This test is only valid when the sensor is completely dry, a wet sensor will always fail.

If it checks out, another possibility is water trickling over the sensor, the sensor only detects water vs air and has no way to determine if the water is trickling over it and it is not "wet" or if it is surrounded by bubbles and not actually dry.