A
AIJ
My boiler stops sending hot water to the taps and CH when hot, even with cold rads and the hot tap open. The pump gets very hot and there is a loud clicking noise from that area. There is also water drip from a serrated bolt in what looks like a pressure release valve (pmax 4bar) just above the pump when this happens. My plumber says I have a sticking spring above the diverter valve (replaced once). I have seven rads controlled by thermostatic valves and one towel rail left permanently open (no room thermostat), and wonder if there is a by pass problem. Also the pressure cannot be pumped up when this problem occurs. My plumber has been called in several times this year but the problem persists. Is it time to replace the boiler (10 yrs old) or is there a cheaper solution?