my worcester 24cdi boiler bangs when running hot water .
sounds like a plane taking off
then makes lots of gurgling sounds then shuts off seems to reset and back on again .

Brian r, August 2010

Thank you again for all your help Carefree
i will give that a try and fingers crossed it helps me work out the problem .

thanks again .

Brian r, August 2010

A way to check if the expansion vessel is okay.
Pressurize to boiler to 1 bar and turn on the heating, as the boiler warms up the guage shouldn't raise above 1.5 bar (This also is dependent on system size).

If you find it rising up to 2.5 - 3 bar as the heating gets hotter, it would indicate that the expansion vessel would need recharging, if that is the case, it explains where the pressure is going, out through the prv.

Carefree, August 2010

thank you again carefree

no visaul leaks that i can find .
will check the pressure relief valve .
and see if that is sticking .
mind you since i pressurised the boiler the banging and gurgling has not happened.
could it be a problem with the EXPANSION VESSEL someone said to me if loosing pressure it could be that .
thank you again for all your help so far

Brian r, August 2010

If it loses pressure, check the pressure relief valve, aav (sticks out through top left of boiler chamber) any visual leaks on the boiler/system.

Carefree, August 2010

hi ya carefree

thanks for that.
i was running it unpressurised as you can with this boiler
i have now pressurised the boiler banging now stopped but looses pressure .

but the sound did not seem to be comming from the pump

Brian r, August 2010

Quite possibly a pump fault, or a gas modulation problem.

Try running the heating, if it bangs too, it's the pump.

Carefree, August 2010