I am fitting a thermostatic shower valve into a stud wall.

The feed pipes will be surface mounted on the other side of this wall
(as they will be hidden at the back of a cupboard).

I got a couple of male 90° 22-15mm compression couplings to fit onto
the end of the pipes and up into the valve hot and cold inlets. This
way the pipes can go straight through the wall at a right angle.

When fitting the 90° couplings to the valve, how do I make them both
point in the correct direction (i.e. at right angles to the wall, so
they meet up with the feed pipes) when they are fully tightened?

When dry fitting to near maximum tightness, they end up pointing in
completely different directions, neither of which is 90° to the valve
body!

Do I cut then ends so that they point where they should when they
"ground out"?
If so, how do I calculate this?

Many thanks,
Deano.

deano wrote:
I got a couple of male 90° 22-15mm compression couplings to fit onto
the end of the pipes and up into the valve hot and cold inlets. This
way the pipes can go straight through the wall at a right angle.

When fitting the 90° couplings to the valve, how do I make them both
point in the correct direction (i.e. at right angles to the wall, so
they meet up with the feed pipes) when they are fully tightened?

Assemble everything before you tighten up. Use a spanner or grips
to hold the things while you do them up.

"Chris Bacon" wrote in message
...

Assemble everything before you tighten up. Use a spanner or grips
to hold the things while you do them up.

You're not reading the OP's question right. What he is saying is that when
the 90 degree bends are hand tight they do not point in the desired
direction i.e. backwards. I had a similar problem to this when I installed
a shower pump and needed the bends to point at a certain angle. I tried
PTFE (no good), waxed string (no good) and finally a suitable sized fibre
washer(s), worked perfectly and has done for over 5 years to date (touches
wood!).

HTH

John

"deano" wrote in message
ups.com...

I got a couple of male 90° 22-15mm compression couplings to fit onto
the end of the pipes and up into the valve hot and cold inlets. This
way the pipes can go straight through the wall at a right angle.

I think people are having trouble working out what you're trying to do. The
only explanation that makes any sense to me is if you're somehow trying to
attach the compression elbows directly to the shower valve compression
fittings*. Lord knows how you'd achieve this. What you're supposed to do is
attach the shower to 15mm pipe using the compression fittings normally
supplied.

So if you use short sections of 15mm pipe between your elbows and the shower
valve Bob will be your uncle.

* Don't tell me it doesn't have compression fittings! All showers do, don't
they?

Mark

deano wrote:

I am fitting a thermostatic shower valve into a stud wall.

The feed pipes will be surface mounted on the other side of this wall
(as they will be hidden at the back of a cupboard).

I got a couple of male 90° 22-15mm compression couplings to fit onto
the end of the pipes and up into the valve hot and cold inlets. This
way the pipes can go straight through the wall at a right angle.

When fitting the 90° couplings to the valve, how do I make them both
point in the correct direction (i.e. at right angles to the wall, so
they meet up with the feed pipes) when they are fully tightened?

Hmmm, do you actually mean you have compression fittings (i.e. ones that
use an olive and a back nut to tighten)?

When dry fitting to near maximum tightness, they end up pointing in
completely different directions, neither of which is 90° to the valve
body!

I susspect that one end of your fitting may have a BSP parallel thread
connector and not a compression connection. If this is the case they
will simply screw into a socket and not have any nut to tighten as such.

Do I cut then ends so that they point where they should when they
"ground out"?

No there is not usually any need to go cutting threads (unless they are
too long for some other reason). What you need is PTFE tape and lots of
it. Threaded connections don't have any way of making a water tight seal
by themselves (unlike compression fittings). So you wind many turns of
PTFE tape round the threaded bit and then screw it in (it will be much
stiffer to do up). This will make a water tight connection by itself, so
all you need do is stop turning when the connection is mostly screwed
home, pointing in the right direction, and *not* bottomed out in the
fitting.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

MarkK wrote:
"deano" wrote in message
ups.com...

I got a couple of male 90° 22-15mm compression couplings to fit onto
the end of the pipes and up into the valve hot and cold inlets. This
way the pipes can go straight through the wall at a right angle.

I think people are having trouble working out what you're trying to do. The
only explanation that makes any sense to me is if you're somehow trying to
attach the compression elbows directly to the shower valve compression
fittings*. Lord knows how you'd achieve this. What you're supposed to do is
attach the shower to 15mm pipe using the compression fittings normally
supplied.

So if you use short sections of 15mm pipe between your elbows and the shower
valve Bob will be your uncle.

* Don't tell me it doesn't have compression fittings! All showers do, don't
they?


No. Mostly they have threaded fittings, which need to be attached to
compression fittings to go to copper pipes.

If this is what the OP is on about, i.e. how to get them tight when
pointing in the right direction, the answer is 'lots of PTFE tape and
stop before they are tight'

Mark

Apply plenty of Fernox LS-X thread sealer to the threads. You can then
tighten the fitting until it is at the angle you require, and the
Fernox will set and seal the fitting.

The only slight caveat is that the joint won't be solid, so you should
ensure that pipework either side of the fitting is well fixed.

LS-X is far better at sealing threads than PTFE!

"deano" wrote in message
ups.com...
I am fitting a thermostatic shower valve into a stud wall.

The feed pipes will be surface mounted on the other side of this wall
(as they will be hidden at the back of a cupboard).

I got a couple of male 90° 22-15mm compression couplings to fit onto
the end of the pipes and up into the valve hot and cold inlets. This
way the pipes can go straight through the wall at a right angle.

When fitting the 90° couplings to the valve, how do I make them both
point in the correct direction (i.e. at right angles to the wall, so
they meet up with the feed pipes) when they are fully tightened?

When dry fitting to near maximum tightness, they end up pointing in
completely different directions, neither of which is 90° to the valve
body!

Do I cut then ends so that they point where they should when they
"ground out"?
If so, how do I calculate this?

Many thanks,
Deano.


I would use fittings with a tapered thread.
Baz

Baz wrote:
"deano" wrote in message
ups.com...
I am fitting a thermostatic shower valve into a stud wall.

The feed pipes will be surface mounted on the other side of this wall
(as they will be hidden at the back of a cupboard).

I got a couple of male 90° 22-15mm compression couplings to fit onto
the end of the pipes and up into the valve hot and cold inlets. This
way the pipes can go straight through the wall at a right angle.

When fitting the 90° couplings to the valve, how do I make them both
point in the correct direction (i.e. at right angles to the wall, so
they meet up with the feed pipes) when they are fully tightened?

Don't fully tighten them.

That is the point.

Fill the threads with hemp and putty, PTFE tape, theradloc or bits of
your hair soaked in beeswax.

Then screw them obnly as afr as they need to go.

"The Natural Philosopher" wrote in message
...
MarkK wrote:
"deano" wrote in message
ups.com...

I got a couple of male 90° 22-15mm compression couplings to fit onto
the end of the pipes and up into the valve hot and cold inlets. This
way the pipes can go straight through the wall at a right angle.

I think people are having trouble working out what you're trying to do.
The
only explanation that makes any sense to me is if you're somehow trying
to
attach the compression elbows directly to the shower valve compression
fittings*. Lord knows how you'd achieve this. What you're supposed to do
is
attach the shower to 15mm pipe using the compression fittings normally
supplied.

So if you use short sections of 15mm pipe between your elbows and the
shower
valve Bob will be your uncle.

* Don't tell me it doesn't have compression fittings! All showers do,
don't
they?


No. Mostly they have threaded fittings, which need to be attached to
compression fittings to go to copper pipes.

All the ones I've seen have threaded fittings that enable you to connect to
15mm copper pipe using the supplied nuts and olives. If they aren't
compression fittings then the Pope is not a Catholic. Perhaps if you're
talking about something else you could illustrate by pointing to appropriate
examples at Screwfix or BES?

Mark

I wrote:
I am fitting a thermostatic shower valve into a stud wall.

Sorry for responding so late on this.
Thanks for all the good replies by the way, it seems I was not alone in
this!!!

Having spoken to the kind chap at my local plumbers' merchants, I was
advised thus...

If using 90° Male 'Irons' (they are not compression fittings but male
threads that fit into the female threads of the shower valve. They no
longer seem to be supplied with any valves as manufacturers have
realised they can't account for the angle required by the feed pipes
for 'ALL' installations and it's cheaper to just not include them!)
using plenty of PTFE tape (or alternatives) is the answer.

Wrapping lots of it on, and perhaps creating a 'taper', near the
knuckle, by twisting the reel, as you wind it around, means the seal
will be watertight, even when the fitting is not tightened to its
extreme. Thus, the elbow can be rotated to suit the position of the
feed pipes.

Even so, this does take a bit of practice to get the right balance
between adjustability and watertightness, and it means you have to be
able to do a 'wet test' before sealing the valve up into the wall with
WBP ply, plasterboard, tiles etc which is not always convenient.

A better suggestion for this situation (and the one I used) is to
always use 'straight irons' (like compression straights but with no
olive or backnut on the shower-valve-side of the fitting).
This can be fully tightened, with PTFE, into the shower valve, without
any doubts about leaking.
To get the 90°, 45° or other degree angle pointing in the direction
of the feed pipes, simply use a 'Street' or 'Stem' copper fitting (of
the desired angle elbow) in either 15, 22 or 28mm. These are fittings
which have different diameters on either side i.e. one side 'holds'
22mm tube while the other 'is' 22mm. In my case, I used 22mm, 90°
street elbows... the 22mm side slotted into the straight-male-iron,
rotated to desired position and then compression fitting tightened,
locking it in place... then other side recieved small length of 22mm
tube soldered and linking valve to feed pipe locations. It's a bit hard
to explain without diagrams, but by using "Street" fittings, any
situation can be dealt with, without the doubt of leaking PTFE joints.

Hope this is useful to someone and thanks again for the replies.

rgds,
deano.