8mm copper to 15mm plastic connector. Possible?

31 Oct 2019
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United Kingdom
I have recently moved house and would like to move a radiator from a side wall, to one below the window as is more pleasing to the eye.

I understand why it was not placed under the window, as my house is old and has concrete flooring so would be difficult when it comes to the pipework. Anyway... I want it moving.

I have worked with plastic JG speed fit piping in my previous house (15mm), and would like to do the same again. As the radiator is only moving about 2 meters from where it currently sits, it seems a convenient way of doing this.

However, it looks like there may be a problem straight away, as the current pipes are 8mm microbore that I would like to cut and connect to 15mm plastic.

There does not seem to be any metal to plastic connectors for this (unless I'm just not seeing them).

I have however found this at screwfix that might work. Does anybody know if I can connect 8mm copper to 15mm plastic using this:


If this is possible, I'm assuming that both immediate pipes will connect using olives (including olives on the plastic piping). If this is correct, once connected to the 15mm I'm good to go, yes?

Thanks in advance! Screenshot_20220220-142754_Samsung Internet.jpg
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Yes ,you can use it. You will need pipe stiffeners in the plastic pipes.
Will look unsightly on show though.
Better to solder 8 mm copper pipe in my opinion .
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I will be creating a channel in the flooring to hide the pipes, so it will be a cleaner look.

A couple of responses say to solder the metal pipework. I have never done that before, so was hoping that the connector would be enough when used with an olive?

Also, are the responses saying to use a pipe insert with the plastic pipe in the connector?

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