I changed the diaphragm on the diverter valve of biasi 24s a couple of years ago and found it quite easy but now the valve is leaking where it meets the big circular diaphragm casing. I have got a service kit for the valve on its way. Is this difficult to remove the whole valve. I only had to switch of water at the mains and drain hot water for the diaphragm, do i have to drain the central heating for changing the diverter valve or service it. any instructions would be great. Thanks
