After a shower a few weeks back, the pressure relief valve started pumping all of my fresh water into the canal. I have a shurflo 4901 - 4215 pump (30psi), a 5litre Zilmet accumulator, and a 3 bar prv.
I replaced the PRV for a similar 3 bar (with guage), and the problem still occurs, in that I switch the pump on, and if no taps are open, the PRV operates and start letting water go (the guage reads appx 3.2, at its peak). I have cleaned out the filter between the tank and pump - with no joy. I have tried adjusting the pump pressure screw (both clockwise and anti clockwise, and still the prv cuts in. I have tested the accumulator pressure (just before the PRV cuts in and its appx 20psi). I am have now got to the limit of my knowledge (not that it was high before), and am totally lost what to do next.....any ideas?