I also have this problem.
new cartrigde will cost me £78.58
how do i know whether i need the grey cartridge or not
Mike
June 2011
You will find the water is working around the seal because it is breaking down. Replacement is the only way. I have tried to find a appropriate seal its a needle in a hay stack unless the designers are prepared to give away their suppliers. E bay were offering a new cartridge for £75 one in one out. easy to change but take your time remember the positioning of the dis assembled items.
Sumbers
May 2010
I have the same problem we think that it is a perished rubber ring or the pressure has got too high as yet we have not fixed as trying to get rubber washer to fit