dont do it your self unless you are confident. you need to have the system empty and an open end before you recharge it otherwise you may stretch\split the diaphragm inside the vessell.
MIKE
October 2006
there is a valve on the vessel same as a car tyre use a foot pump or push bike pump
hi-spec plumbing
October 2006
I can answer this question...
potterton puma 80 no pressure in expansion vessel?