Hi everyone, Hope someone can shed light on this problem. I’ve been and changed bath taps For a client by first isolating the cold mains. I then opened the kitchen mixer tap to drain both hot and cold water and while that was draining, I went into the bathroom and opened the separate hot and cold bath taps. The water started to slow down but the hot took a little longer to stop (no more then 1-2mins). So I proceeded to remove the bath taps then suddenly the hot water started running from the pipe. At this stage the tap was already removed so I had to place my finger over the pipe to stop the water. I asked the client to open the taps downstairs to which he replied “they are already open” He then went into the loft to isolate the hot water outlet from the cylinder via a gate valve he had installed by the installer of the cylinder. After replacing the taps, I asked the water to be switched back on and all looked well till the clients son shouts out that the boiler is leaking. I went up into the loft and saw that the cylinder was leaking from the heating outlet into a polythene sheet made up into a box. I isolated the cold mains and although the cylinder looked fine externally, the top had come away and the secondary outlet that was unused had moved away from its original position and poking out into the insulation of the cylinder away from where it should be. It was obvious that the cylinder had imploded and went near back into shape once the water was put back on. At this point the client says to me “not again” He then explained that that’s the second cylinder that’s imploded the first one five years ago and now this one. Apparently the first one imploded after the client changed a washer in one of the taps. The cylinder is installed in the loft and it’s a detached 4 bedroom property with 2 bathrooms. On inspection, the only thing I noticed is that the expansion vessel is installed on the hot water outlet instead of being installed after the combination valve on the cold inlet as illustrated on the manual Would this void the warranty and cause such problem?