Hi,

I have a problem where by the pressure on my boiler keeps hitting 3 bar & releasing all the water outside.

I've had 2 plumbers out who can't find the problem, both say there is nothing wrong with the expansion vessel & have re charged it.

I have an issue now that because the boiler turns itself on every hour for about 1 minute, i wake up in the morning & the pressure has gone from around 1.5 bar back upto 3 bar again, and thats with no heating on overnight..

Help please!!

Craig, January 2012

Nothing to do with expansion vessle, For pressure to increase, water has to get into system, Otherwise pressure will go up when system on, down when off. Check your fill loop valve, if not off fully, pressure will creap up. If valve ok, try disconnecting, should have a non return valve in line anyway, to stop water going from system back into mains supply, SO it should be possible to disconnect, I have however know some non returns to leak out, from the mains supply. BUT valve should stop any getting to system. Should be about 1 bar cold.

SD, January 2012