Can't get concealed thermostatic cartridge out

31 Aug 2022
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United Kingdom
Hi there

I have been trying to get our concealed thermostatic cartridge out so I can descale it, I've got this far but the cartridge just won't budge. It looks like there is a grub screw but no way to access it, no hole, and looks like it may just be a locator screw. I've tried pulling, turning, just cannot get it out. Pic attached.

Currently soaking with vinegar as best as I could get it in there but doesn't seem to have made a difference so far...

Any help/thoughts greatly appreciated



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Where retaining grub screws are fitted they are usually at the base of the body of the tap. So that would be on the underside of the brass surrounding you black plastic valve body. You might have to chip out some of the plaster to locate it, if there is one.
Thanks for the response, I don't think that's the case though. The isolation valve is under. (pic attached).


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