I've recently had to replace a shower valve in the Aqualisa Aquarian Thermostatic shower (pre-1999 model), but on turning the water on from the gate valves, the cold water outlet seems to leak. There's a tiny gap between the pipe and the cold water inlet on the shower valve that's leaking when the water's turned on.

Does anyone know how to seal this gap, and what I could use to do it...or do I need to call a plumber out?

Ant., June 2007

Sounds like the pipe has pushed in so not contacting with the 'i' ring in the mixer cold water inlet. probably cause is the plastic grab ring has broken or become ineffective. Strip the shower down and remove the rear case by unscrewing it from the wall. Renew the plastic grab ring (available direct from Aqualisa) by removing the old one and pushing on the new one pulling the pipe outwards at the same time. Ensure that between 48-50mm of pipe protrudes from the wall. Reassemble, coat the pipes with a thin layer of silicone grease and the pipe should then push the cartridge on and seal with the 'o' ring.

Stephen, December 2007