Beginners tips for plastic plumbing

Hi,

I've done all my previous plumbing work in copper, and I'm perfectly happy using end-feed, yorkshire and compression fittings.

But I'm a n00b with plastic pipe. My basic understanding is this: It shoves as-is directly into push-fit fittings, where an o-ring in the fitting provides the seal. But you need an insert for use in compression fittings, to prevent the pipe collapsing under the olive. Is that basically correct?

I have some old recovered plastic pipe here, which I'd like to re-use. It is marked "Hepworth BS7291/2 class S 15 x 2 mm H+C services and Central Heating 12 bar/20c 7bar/82c" and has metal inserts on some of the ends which went into copper compression fittings. These are plain inserts with no o-rings or anything. The olives are still there, and I guess I can probably cut the olives off and re-use the metal inserts.

Is all flexible plastic pipe basically the same, or are there different 'systems' which require matching fittings and inserts etc? Or is it just the fittings which come in different 'systems', and each family of fittings has it's matching inserts?

I'm a little confused about the different systems which I can find, for example on Screwfix. There's stuff called 'Pushfit', and 'Speedfit'. Presumably 'Speedfit' is a brand name, and Pushfit' is just a generic term?

I see plastic pipe like this:

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looks a lot like what I have here. It says to use speedfit inserts. Presumably only for compression fittings? Or perhaps for all fittings? Or just for speedfit fittings?

The inserts are here:

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they have o-rings on them! What's that all about? That suggests these inserts form a part of the sealing mechanism, and are not just to prevent the pipe crushing in a compression fitting. So these don't look like the right part to go into a compression fitting. I can't imagine what they are for at all. Surely in a pushfit fitting, the o-ring is part of the fitting, not part of the pipe insert? They don't look to be strong enough to take the squeeze of a compression olive.

It seems to me I'd want plain metal inserts like I have to go into a compression fitting. But I don't see those on the 'Push-fit fittings' page at screwfix.

Looking at copper push-fit systems, I see the cuprofit ( presumably hep2o is similar? ) require inserts in plastic pipe, even in a non-compression fitting. These are marked 'only for use with cuprofit fittings', so I guess they are also not the correct thing to use for a compression fitting?

So what's the compatability story here with plastic plumbing? What inserts do you use with what pipe and what fittings? Specifically, what inserts do I need for fitting this pipe into a compression fitting?

Reply to
Ron Lowe
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Me too until recently, tried Speedfit on the reccommendation of my local plumbing place and I'm very impressed. Probably takes a quarter of the time to install - which is important to me.

Not really. The stuff I used had inserts for use with the plastic pipe, which was used in push fit and compression fittings. The fittings would take copper pipe as well.

Sounds like Hep 2 O. Have a look at thier web site for some good info. Apparently Speedfit is compatable with Hep 2 O and this was the case on the one join I had to do. The inserts I used were plastic.

Don't know, but Speedfit & Hep 2 O seem to be.

I guess so. Thats how it seems to me anyway.

I was told for all fittings and I didn't have any trouble.

The first lot of inserts I had were plain black. I had to go back for some more fittings and they gave me white ones with o rings like your picture.. Apparently its an upgrade to give a better seal?

I was dubious about plastic to copper compression but it worked fine with the plastic insert.

I only had one leak on a fairy large job and that was a fitting dripping. I removed the pipe and the end had been adraded & scratched. I cut the pipe back 2" and reused the insert and it was fine. I did use the proper cutting tool though, I believe thats vital.

Anywho - great fan of plastic now.

Reply to
The Medway Handyman

On Sun, 18 Jun 2006 09:14:58 +0100, Ron Lowe wrote (in article ):

No.

You need an insert for plastic fittings as well. This prevents the tube from collapsing

The pipe is the same, although there are barrier and non-barrier types. For water services, non barrier pipe is OK, but for heating, using barrier pipe is a good idea to prevent diffusion of oxygen through the pipe into the water.

The inserts are manufacturer specific. Plastic fittings have an O-ring to seal and some mechanical means to retain the pipe.

Speedfit is the brand name of John Guest, one of the main manufacturers.

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In the Speedfit system, there are two O-rings - one in the fitting and one on the insert. These are intended to further improve sealing. The fittings also have a twist retaining ring to lock the fitting. It seals without either of these, but they presumably believe that it gives them a marketing advantage.

Each manufacturer of fittings has an insert that works with their fitting, be it a copper or a plastic one. The pipe is standard. You can mix and match fittings but must use the components supplied for the fitting.

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Reply to
Andy Hall

Plastic pipe is fine. Use barrier pipe. It is the pushfit fittings that is the problem. They give more problems than any other type of fitting by a country mile. You can use good quality brass compression joints with plastic pipe using the pipe inserts. They no more, if cheaper, than pushfit. Go this way. Wrap the olive in PTFE as per makers.

Reply to
Doctor Drivel

Until the ceiling comes down.

Reply to
Doctor Drivel

On Sun, 18 Jun 2006 11:13:14 +0100, Doctor Drivel wrote (in article ):

That only happens when you use a hacksaw to cut the pipe though.

Now who did that? Hmm..... let me see now....

Reply to
Andy Hall

Hi Ron I have done a barn conversion all with plastic Hep20 barrier pipe. I have had no problems what so ever. In fact you can even use push fit between copper and plastic... but not chrome plated to plastic since the chrome is a harder metal that copper, so the teeth on the push fit dont bite.

I have a friend who used the double o ring type of fitting and had 2 leaks on a single bathroom job. I told him about Hep20 and he has had no problems... it may have been that he was using it wrongly, but I doubt it as he is very meticulous, but I cant be certain.

Using the correct cutting tool is vital as are inserts within every fitting whether push or compression.

On the note about using plastic pipe but not push fittings I would say the opposite. After all, the braking system on many lorries is push fit and they opperate at much higher pressures than domestic water systems. The only two downsides that I can see to plastic pipes are the potential damage by hungry mice and the lasck of aesthetics present with copper... but then again most plumbing is contained under floors or within cupboards... so go for the Hep2O barrier (or another of your choice) and enjoy the speed at which you can plumb your house.

Calum Sabey (NewArk Traditional Kitchens 01556 690544)

Reply to
calums

Ignore Drivel, he uses a hacksaw to cut plastic pipe then whinges when it causes leaks. There's no inherent problem withpushfit fittings, and across Europe, pushfit is replacing galvanised tube for mains water supplies operated at much higher pressures than in the UK.

The (lack of) experience of one stupid, incompetent, arrogant fool should not put you off using pushfit fittings. Like everything else, cleanliness, clean cuts, using the right tools, following the manufacturer's instructions and patience will produce a decent result every time. Buy yourself a pipe cutter, it's well worth the time saving and lack of aggro.

Reply to
Steve Firth

The message from "Doctor Drivel" contains these words:

Makers recommend wrapping the olives in tape? Cor - where?

Reply to
Guy King

I have been using plastic (and copper) for years as well - I agree entirely with Calum's findings and points, particularly... use the correct cutting tool, you always need to use pipe support sleeves (inserts) try not to use plastic in places liable to rodent attack (and wires for that matter) or sleeve in steel conduit (a right pain if not impossible) the fittings are all based on the O.D. of the pipe being used, be it plastic or copper so are compatible and mixable even on the other end of the same fitting.

I do note, though, that the Copper pushfit available at B and Q (Easyplumb ?) does state "not for use with plastic", possibly / presumably because the grab rings do not grab deep enough to safely use with plastic pipe.

I have been entirely happy with plastic plumbing - and it's is quicker and less wasteful to install - learn and understand the system and install / use as intended and you will be happy too

Nick

Reply to
Nick

Matt, you know nothing this sort of thing. Grab rings fail and hey presto. Many will hold for days then when a tap is shut off suddenly the shock will pop the fitting and a full bore spewing out over the ceiling. Failings tend to be catastrophic. Matt, this is not for your info, it is for the OP, as you are lost case.

Reply to
Doctor Drivel

I know of one site where they stopped using Hep2O because of far too many failures.

Well your experinece id obviopusly DIY, mine is not.

And are built to much higher stadards too.

But drop the pushfit fittings and use brass compression.

Reply to
Doctor Drivel

Flags: Note the white background.

Flags.

Reply to
Doctor Drivel

In their manuals. Cor.

Reply to
Doctor Drivel

Use it professionally and you will think differently. Just avoid the pushfit fittings and all is fine.

Reply to
Doctor Drivel

On Sun, 18 Jun 2006 15:09:49 +0100, Doctor Drivel wrote (in article ):

Be professional about it and read the instructions and all will be fine.

Reply to
Andy Hall

On Sun, 18 Jun 2006 14:41:13 +0100, Doctor Drivel wrote (in article ):

What happened after they confiscated the hacksaws?

... and yours is?

Reply to
Andy Hall

I have, I did and all has been fine, for the last 14 years anyway......

Nearly all my work is "professional" !

Nick

Reply to
Nick

You are lucky then.

Is pipefitting your profession?

Reply to
Doctor Drivel

Matt, there is reason why prfessionals generally avoid the stuff.

Reply to
Doctor Drivel

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