On Thu, 20 May 2021 15:49:23 +0100, newshound
wrote:

On 20/05/2021 13:59, MM wrote:
The cistern service valve is very slightly weeping and so will have to
be replaced. But in order to remove the valve I shall have to cut off
the ferrule at the compression joint end. As it is unfeasible to
actually saw through the ferrule, the usual approach is to saw through
the pipe just past the ferrule. But then the gap between the cistern
inlet and the new service valve is likely to be too large.

So what about fitting a 150mm flexible hose instead? There are several
available, on eBay, on Amazon etc. These have a compression joint at
one end and the usual coupling at the other end to screw onto the
cistern inlet. They are available with or without an integral
isolation valve. I would only choose the latter kind.

I've fitted compression joints successfully before, but have never
used the flexible hoses for anything, so have no experience with them.

But surely the compression joint end is just like any other
compression joint? Should just be the case of using a pipe cutter to
cut the existing copper pipe, then fitting the hose? The only
complication is that the builder painted the copper pipe white to
match the bathroom! But paint stripper should remove it. Plus wirewool
perhaps.

I assume one would attach the hose to the cistern inlet first, in
order to gauge the right distance to cut the copper pipe for the
compression end?

Am I on the right track here?

Thanks.

MM


I am a big fan of using flexible hoses for things like this, only I
would get one with an isolation (also known as service) valve. This is
exactly what I just did when I had to replace a cistern recently.

I find the best way to deal with painted pipes is to scratch the paint
off with a stanley knife blade, held perpendicular to the pipe and slid
axially so that you take off longitudinal strips. When you have most of
it off, finish off with steel wool. You don't want to make deep gouges
in the copper, but superficial scratches are OK especially when finished
off with wire wool. The point about olives is that they deform, and
deform the pipe, when done up tightly, which is why they are tolerant of
surface roughness and pipe tolerances. The female threaded end should
come with a rubber washer to make the seal on the ball valve inlet.

And yes, whether using flexible or solid pipe, fit the pipe to the
cistern first and then "cut and shut" to the existing copper.

Thanks. I've seen the short hose with integral isolation valve for
around £3.50 on eBay or Amazon, but my local DIY merchant may actually
have one on the shelf. I note your comments about scratching the paint
off, but do you not rate paint stripper? Or is it corrosive on copper?

MM