Osmolator eye not working

[Emster]

About once a week the eye does not turn the pump on, i have to wipe it with my finger to get it to turn the pump on. I have another one that has been flawless for 5 years now. Is there anything I can do? Thanks in advance

 

[rvitko]

Try soaking it in vinegar for 4-6 hours and wiping it off with a soft towel. Any film of minerals on the sensor will be read as being in water.