ravenheat boiler?

it most likely the expansion vessel. either it needs replacing as its got a hole in it or it needs inflating. its a vessel red in colour which contains a rubber balloon inside as the water in the heating system warms up it expands causing the balloon to shrink to stop the pipes or safety valve opening. what u need to do is drain the boiler of its water and open the prv valve or open a radiator nut know get on to the top of the boiler u see the tank behind it undo the black cap on top and inflate the tank with a car foot pump to 1.5 bar then close it. remember as u inflate to leave the rad or prv open as the water will push out the vessel. thats really it if it keeps need inflating then u need a vessel gl

kash
October 2010