Leaking cartridge

Hi, my plumber has just replaced the cartridge due to It being stiff and the showerhead dripping. The replacement went in easily however when he turned the water back on there was a leak at the bottom of the cartridge. He removed it and rechecked both of the small (letterbox) shaped seals to make sure they were seated ok and re installed it. Once again the cartridge leaked. The shower has been in since 1994 but has never leaked and the cartridge was only replaced due to the issues I've outlined above. Could it be a faulty part? Or Could it be the machined body (part number 5 on your schematic drawing)? It looks fine but could it have warped over time meaning the seal on the cartridge doesn't sit flush against it? I've included a couple of photos of the old cartridge to try and show you the part we think is leaking. Help!!!!!????
Asked 6 years ago by Rachel
It would be unusual to have a leak at these seals, however they need to be checked.

First to make sure they haven't fallen out as you push the cartridge back but the more usual problem is one of the original seals to be left in place and when the new cartridge is offered up it squeezes into place with the new seal which means it won't seal peoperly.

We have a video about fitting this cartridge (See Below) these seals are mentioned at about 2:30 into the video.

www.youtube.com/watch?v=bvng57EMQCI

Hope this helps.

Answered 6 years ago by George Thomson

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