I have a friend who lives in Quinns Rocks and is on a shared bore. In the last year we have replaced 3 solenoid coils on the same valve because they have corroded and become stuck open.
I haven’t seen this happen before, but it seems that the minerals in the water (or perhaps the salt) may be corroding the solenoid piston and causing it to fail.
At the moment I don’t have a suitable solution, but it may be that we need to find a solenoid that does not have any metallic parts. You obviously can’t change coils every few months so there must be a better way to hit the problem.
If you have had any similar problems then I’d love to hear about it