The pull out tap has gone loose in its socket, and the seal has disappeared. As there are grooves in the socket and tap shaft, I assume that an o ring will fix it. The o ring looks to be about 22-23 internal diameter. I would like advice if that is correct, and that the combined hot and cold water tube is a push fit, so as to get the o ring on. I have read a repair report that mentions in passing that you can cut off the tube and refit by softening in hot water and pushing back on. I would welcome comment as to whether that is it, and that there isn't a fiendish Eriba design that makes the job difficult.
Thanks
Nick