Disclaimer: This post was originally posted by Hero Member, mjb8743. This user is located in Zone , South NJ, Garden State. This was originally posted on July 6, 2013.
To be sure it's not a sensor problem, have you tried the glass of water test? Halfway fill a glass of water and (remove the sensor from the box; it will be dripping...) slowly lower the cup into the glass. The water should stop. If it does, check that your tube is all the way down in the box and the sensor is fully seated on the tube. If it's raised even a little, that could make the sensor keep running. The tube shouldn't be sitting straight up... it needs to be angled into the box corner.
If the water does not stop when lowered into the glass, the diaphragm likely is not functioning as it should. It may be crusted with minerals, etc. You can try soaking the entire sensor in white vinegar for several hours or overnight. Swish it around really hard to loosen any debris.
If you're at all handy, you could loosen the 3 screws a little to give better access for the vinegar.
If you're really handy, you could carefully dismantle the sensor head, MAKING NOTE OF PLACEMENT AND ORIENTATION OF THE PARTS, and soak them. Using a soft toothbrush, clean the diaphragm and the orifices. Rinse the parts in clean water.
When reassembling, screw the 3 screws in a sequence until all are snug but not over-tightened... remember the sensor is plastic; you don't want to crack it from over-tightening.
I don't know how old your system is, or the water quality passing through the sensors. It is essential that you have a flushable 150-200 mesh filter in the system, and occasionally (annually??) clean the sensors as described above.
Mickie
