Reestit Mutton wrote:

There are 15mm hot & cold shower tails behind the bath which I need to
step up to 22mm as this is the size of the shower inlet.

ok

I'm using compression joints and I've been told that I need to use a
22mm joint with a 22x15mm internal reducer. I have all this stuff and
there is only one way that the internal reducer will fit into the joint
and that is if I throw away the olive that comes with the joint.

That won't work - the olive is the vital part of a compression joint.

Everything seems to fit snugly but, when everything is tightened, the
15mm pipe is not gripped tightly. i.e. I can pull it out of the joint
with my fingers.

Now, even a numpty like myself knows that this is just plain wrong.

Yup

Is there a specific way this joint and reducer needs to be fitted or am
I missing a vital ingredient that does the job of gripping the 15mm pipe?

Just to recap, I have the following:

22mm plastic pipe with insert
15mm plastic pipe with insert
22mm elbow joint
22x15mm internal reducer

OK, having some trouble visualising exactly what your "reducer" looks
like are its ends male or female?

Have a look at http://www.bes.ltd.uk for some pictures...

You typically get a number of different types of reducers: reduction
fittings - these are normal fittings but have different sized female
ends to suit your pipes. So for example a 22x15mm reducer would have two
compression fittings, a 22 on one end and a 15 on the other. Look at
product code 6714 on the BES site. This you would use with olives either
end like a normal fitting.

You can also get fitting reducers - but these are not common in
compression. Here one end is designed to fit into a normal fitting (i.e.
it is a male end) and the other end is a fitting of a different size.
Product code 6788 would be an example of a solder fitting of this type.

There is also a thing called a reducing set that is designed to work
with compression fittings to adapt the socket on one side to a smaller
pipe.

Since you have plastic pipes, perhaps a straight reduction fitting like
10513 would be simpler - so step up to 22mm plastic, and then use your
compression elbow.

--
Cheers,

John.

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