My valliant boiler has been having low pressure of late and when I turn the knob to increase the pressure it stays on there for a few days and the pressure falls again. 2 days ago, the boiler started leaking from the bottom.I've just realised that when I increase the pressure the leaking is more. 2 days no heater. Any thought please. I spoke to British gas but the call out charge is astronomical. Any help will do before I commit almost 200 pound for a repairer.Thanks
If it's leaking thru a fitting then u can probably get away with tightening it a bit
That's why we use a forced air system for heat
u only turn the tap on (to increase the pressure) for minutes not days. the leak ( if it is in fact a leak and not jsut overflow) may not be from the bottom - it just ends up there. but u probably knew all that already. i should have thought any plumber could fix it for #50. ring around. why british gas?
It is most probably because the water pressure relief valve is leaking, and running out of the overflow pipe. This valve holds the pressure in the system. It has failed and needs replacing. If you can locate the valve,(Which may have a red cap) then turn water of to the boiler, and Remove the valve. You may have to remove the side panel to get enough access. Get a replacement valve with the same prssure which is stamped on it, and fit it in place. You can get a valve from most Plumbers merchants.never exceed the correct boiler water pressure which can cause this valve to fail.
are you sure it is leaking from the boiler and not the pressure relieft valve? normal running pressure for a bouler should be less than 30psi usually in the 15-20 range. If it is the boiler it might be cracked and need replacement, That is unlikely unless it had been dry fired recently. Most likely it is the relief valve which could be blowing off excess pressure for any number of reasons ranging from faulty fill valve, bad expansion tank, leak on a hot water coil, etc.. Id call a serviceman or a local plumber who might be able to give you a price on replacement if thats what you need. Could cost 5000 - 10,000 for a new boiler.
