cutting pipes for shower - no space

[Spat]

more gravity fed shower fitting questions! I need to cut pipes to branch off to the shower but have very limited space, what's the professional's approach? the space in which to use a pipe cutter is about 1cm from other pipework that can't be moved and obviously I'm loath to pull the pipes about too much.

Also, I'm planning to branch off existing bathroom pipework, the instructions for a mira realm says cold must come from a cistern, I'm not sure if the cold is from mains or not, is that likely, or even something to worry about? It's certainly at higher pressure than the hot water.

lastly (ahem) anyone got experience with a waterford? I want a decent unit, but Mira's are too expensive. Thanks.

[Wingedcat]

I would certainly answer your second question before worrying about your first - that is, what sort of shower you are going to end up with, as each have different (and v. specific) requirements regarding the type of water supply. For instance you certainly could not connect mains cold water to a pumped shower.

Regarding the pipe cutting dilemma, if you are joining copper to copper with soldered fittings I would have no hesitation in using a hacksaw or other primitave cutting device, anything that doesn't distort the roundness of the pipe basically. (Make sure you wash out swarf first though before connecting to your new shower).

(Sits back and awaits furious admonishings...)

If you've got plastic pipe or are going to be using push-on fittings, I would recommend the use of a proper pipe cutter, which will necessitate (it seems) some rearranging (or further disconnecting downstream perhaps?) of the pipes. Often if you make one cut further back in a pipe run, the pipe will flex giving you plenty of room to get a pipe cutter to it.

[David Hansen]

On 3 Oct 2006 05:27:48 -0700 someone who may be "Spat" wrote this:-

It depends on which part of which country the house is in and the age of the plumbing. Perhaps 50/50 over the whole of the UK.

It is very much something to worry about. Imagine the situation where someone is showering under a non-thermostatic shower when the mains water fails for some reason, but the gravity fed hot water continues for some time. They are likely to be scalded, perhaps killed.

Then it is highly likely to be from the mains. Follow the instructions, someone went to the trouble of writing them for a number of reasons including your safety.

If the shower is thermostatic and you wish to trust your safety to a mechanical gadget, rather than doing the plumbing properly, then a pressure equalising valve can be fitted to make the thermostatic valve work somewhat better.

[Spat]

thanks. I'm going for thermostatic mixer from G fed water, no pump.

Plastic would be more convenient as i need to make a few turns (2X90 degree) , but can it attach directly to the shower unit? Reading through posts here tho, many people seem to think copper is the "right" way and it will make cutting easier if i can get away with a hacksaw. The pipe cutting is to put T pieces in so I guess they'll be copper anyway. To give enough space to fit the pipes together, the chases in the wall will have to be pretty deep though which seems an advantage of plastic's flexibility.

[Spat]

Thanks. I guess the water is at mains pressure then, my question was prompted because nearly everywhere I've read, instructions for fitting a thermostatic mixer shower from GFed suggested tapping off from existing bathroom piepwork was ok, just the Mira instructions stating different. Looks like I'll have to run a huge line from my loft water tank, a right pain!

[Dave Fawthrop]

|more gravity fed shower fitting questions! I need to cut pipes to |branch off to the shower but have very limited space, what's the |professional's approach? the space in which to use a pipe cutter is |about 1cm from other pipework that can't be moved and obviously I'm |loath to pull the pipes about too much.

I would use a hacksaw or a fine toothed hacksaw blade and some gaffer tape round the blade to form a handle, with the cut cleaned up by a fine file. A miniature hacksaw might also work OK again followed by a fine file.

[The Natural Philosopher]

Thats enough to get a small rotating pipe cutter in, and don't be afraid to bend copper pipes a bit.

Or you can use a dremel and a cutting disk..

I have often replaced quite large sections of pipe just to get around this problem.

Don't be afraid to cut away madly to allow a job to be done, you can always put pack stuff later.

Oh. I don't like the sound of that...

My only complaints on chap shower units have been the plastic shower HEADS. Our mains pressure simply blows them apart..literally. Only metal heads seem to be able to handle it.

The mixers themselves - well some are a bit plasticky and have wobbly taps, but they all work OK.

[The Natural Philosopher]

Only on the basis of the burrs sawing introduces, and the difficulty of removing them in a tight area. Its bad enough cleaning up the pipes with wire wool, in a tight place, let alone BURRS.

Yup.

[Bob Mannix]

When you do so it "should* have a separate, slightly lower position than the outlet for the hot tank. This is so (as suggested elsewhere) if the water fails and the tank empties, the hot water runs out first so you don't get scalded. It's standard for pumped showers too.

[The Natural Philosopher]

I prefer copper because it adds support to the shower mixer. If you can solder one joint, you can solder 6-8 allright..and right angle bends are all in the days work. Then with plastic supplementary bonding raises its ugly head...and as you have pointed out how to attach it to the shower unit..

[The Natural Philosopher]

Blimey. You expect to not be able to jump out of a scalding shower AND not be able to limit your hot water tank to an non lethal temperature.

Or are you merely a Nu Laber supporter who thinks that his intelligence is infinitely greater than they Public At Large,, who must be cocooned from their own stupidity as they are incapable of Getting Anything Right without inspectors and legislation to enforce it?

You hafta larf doncha. They don't care about sfatey, just not getting sued.

Yawn. All together now

"Ring a ring of Roses A Pocket full of Posies Atishoo! Atishoo! We All Fall Down!"

[The Natural Philosopher]

I've run showers off mains cold and tanked hot. They work,. Its illegal though because any blockage can cause the cold water to backfill the hot water tank and cistern. I think a non-return valve would fix that. Of course its vile, because anyone opening taps anywhere alters the balance, and the shower temp is all over the place. Even thermo showers have a hard time coping.

In fact you can get curious effects like this on full pressure systems too.

As I discovered when I installed a mixer on ours, before fitting the shower head. I left the head blanked off, but forgot to switch the shower off after leak testing..it became a matter of pure luck as to whether any given hot or cold tap would deliver hot, or cold water..in fact most did both, at different times..

[Christian McArdle]

Supplementary bonding is easier with plastic. It doesn't need any.

However, I still agree that showers are best done in copper, purely because of mechanical strength.

Christian.

[The Natural Philosopher]

Ah. Thats good news then.

[David Hansen]

On 3 Oct 2006 06:17:34 -0700 someone who may be "Spat" wrote this:-

It can be done with a thermostatic mixer. However, it is still better to have a separate cold feed.

If the shower is some way away from the tank.

[David Hansen]

On Tue, 03 Oct 2006 14:41:15 +0100 someone who may be The Natural Philosopher wrote this:-

What I can or cannot do is irrelevant. Not everyone can jump out of scalding water.

People have died at modest temperatures. It is not just water at say

120C that is lethal.

Excellent, a personal attack. Always mildly reassuring.

[Brian Sharrock]

I now it's been a long time since I went to school ... and perhaps with the nu-Labor modular exams, things have changed; -- but IIRC "water at say 120C " used to be called 'steam'! [at Standard Atmosphere and Pressure for the pedantic!]

[The Natural Philosopher]

Which is why it is pretty much regulation to set your tank stat at no more than 60C.

Less an attack, than a random observation.

Its widely known that hot water should be between 45 and 65C..and should be at the lower end of the scale where elderly and physically disabled people are likely to use it.

Its widely known that the reasons that its not good to mix high and low pressure cold and hot water in any kind of tap except one where the mixing is done externally to the device, is because if the problems of backfilling header tanks.

You are also far more likely to jump into a bath of scalding hot water than be able to physically walk into a shower, have it go scalding on you, and not be able to walk out,.

In short your arguments don't stack up, you are merely parading silly ideas as if they meant something and are in fact a total tosser.

Ergo, you probably voted Laber.

>

[The Natural Philosopher]

Oh don't be silly. Like Humpty Dumpty, his words mean what HE wants them to mean.

[David Hansen]

On Tue, 03 Oct 2006 21:53:25 GMT someone who may be "Brian Sharrock" wrote this:-

The bit in brackets is the important bit. While one is unlikely to come across water at more then 100C in domestic circumstances that does not mean it doesn't exist. It is found (in pipes) in some commercial/industrial settings. If the water escapes from the pipe then obviously it turns into steam and a little boiling water. This sort of thing is best thought of as liquid steam and treated with as much respect.