15mm Plastic Compression Fits

20 Jul 2008
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United Kingdom
I need to remove a plastic compression fitting from the water feed pipe to the ensuite toilet. The compression fitting is attached to a copper pipe that connects into the bottom of the toilet via a valve. I ultimately want to replace the copper pipe with a flexible hose.

Thanks in advance for any help.
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Turn off water
Drain down by opening a downstairs tap
Undo plastic nut and remove also where it connects to toilet
Attach your flexibility connector to toilet
Cut the copper in appropriate place (so it fits in the flex)
Tighten then test.
Thanks for the replies.

Unfortunately the nut on the plastic connector will not undo.

There is a valve already fitted to the toilet.
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That's a service valve and it's brass they can be a little tight just need to try harder. Make sure you get a decent grip of the valve with some grips then use an adjustable spanner.
Thank you for your reply.

There is a very slight leak at the right angle bend in the copper pipe.

Hence my need to replace all of the copper. I cannot remove the copper pipe from tge plastic compression fitting at the bottom of the photo.

Thank you for your patience.
Ah. Sorry I didn't see the fitting in the wall. It's not clear but looks like a polyplumb push fit fitting. Can you not cut the copper below the leak and then add your flex?
If it is polyplumb you can unscrew them but they can be tight. I sometimes use two pairs of grips on them but very gently.

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