I have a Potterton 100 / 100e. The boiler water overflow is constantly flowing water, and the system water pressure was slightly in excess of 3 bar. I turned the water inlet off, and the power off to the boiler to reset it. I then turned the power and water back on, and the pressure is approx 2.5 bar, though the overflow is still flowing water indicating that it is over pressurized. The pressurize overflow is now always running if the water inlet is on. How can I stop the overflow?

nooneels, May 2009

I haven't done anything to it really. It has been working fine, then today for no apparent reason it is indicating that it is over pressurized via the system pressure gauge, and activating the safety pressure relief valve. Whenever the main inlet water is turned on, then it constantly overflows due to the safety pressure relief valve being activated.

nooneels, May 2009

has your filling loop been disconnected

b, May 2009