speedfit insert for copper pipe

1 Apr 2008
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United Kingdom
I'm joining a speedfit junction on to a 15mm copper pipe.

the insert seems a little loose in the copper

should i be using a different insert (or a different junction!) as I'm joining to copper rather than plastic?


thank you

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The loose one will be fine, or better still just leave it out cos it doesn't need one. It's a copper pipe.
You dont need the inserts in copper pipe... Just make sure you cut the copper straight and de-burr the ends...
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I put a speedfit cap on it with an insert - it leaked.
took the insert out, and put the cap on again - it's sealed.

I can go and have a bath now, and will continue my foray into the world of plumbing tomorrow

cheers all

It shouldn't have leaked, even with the insert in.

It sounds like you didn't have the fitting pushed fully home, I strongly suggest that you turn off the water, open the taps to release the pressure and double check that you have pushed all your fittings fully home. If you are in any doubt, do it now and don't leave it to chance. I find that the end stops are hardest to push on fully BTW.
The inserts are not designed to be inserted into copper, different wall thickness, therefore could cause leaks ... They are designed to be a tight fit on the inside of the speedfit pipe.. They will be loose in a copper pipe..

Inserts in all flexi plumbing systems are there to maintain the circular integrity of the pipe under pressure.. Copper maintains its own shape through strength of the tube...

95% of all flexi plumbing problems are caused by bad installation, and that includes plumbers and diy...
With sincerest respect Saltire, how can the presence of a redundant insert in a copper pipe cause the fitting to leak? It would only serve to stop the pipe being pushed fully home by a few mm but the pipe should still be well past the main seal in the fitting. I'm just concerned that the OP isn't aware of the importance to ensure that these fittings are pushed fully home.
I agree it is important the pipe be fully inserted, but something that shouldn't be, and doesn't fit properly, shouldn't be there...

The manufacturer says you dont put these inserts in copper for a reason...
Sure - reason being that it would do absolutely nothing. Not cause a leak, not stop a leak... :rolleyes: :rolleyes:
Viessmann have inserts for copper pipes!!!

95% of all flexi plumbing problems are caused by bad installation, and that includes plumbers and diy...

Where did you find this figure of 95%?

Or did you calculate it from some figures that you found? If so, where?
I realise the problem was that the pipe itself was sliding down - so the fitting wasn't home when I thought it was - I think I'll mark the (plastic) pipes for the next few at least to make sure they are home.

Thank all

I ALWAYS mark plastic pipes before pushing them into fittings!


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