15mm Speedfit pipe

Discussion in 'Plumbers' Talk' started by Stan Lee Blade, Jan 4, 2018.

  1. Stan Lee Blade

    Stan Lee Blade Active Member

    My son has asked me to help install a new radiator as I have the skills required to fit and solder the copper pipe.
    Radiator fitted on the wall. Boards taken up on landing, then to find the pipes running to bathroom towel rail in 15mm plastic Speedfit pipe ( this is what I intend teeing off from )
    The stubs running up to the towel rail are in 15mm copper so I guess it’s changed under the floor ( can’t see that bit as it’s on the other side of joist in bathroom)
    I will admit I am not very well advised on Speedfit pipe , however the guy from the plumbing centre has sold us two 15mm compression tees and the Speedfit pipe inserts .
    I can see how these go together. Once the tees are fitted, I will then work in copper to the radiator valves.
    This will only require a short length of copper pipe and one elbow.
    What is there is there, so i can only work from that.
    I guess I could run it all in plastic to the TRV but I don’t think plastic pipe will look very tidy.
    Any advice on what I should be aware of whilst connecting compression to Speedfit would be appreciated .
  2. CraigMcK

    CraigMcK Well-Known Member

    I guess one question, why did he not just give you speed fit Tee's, that would have made life a little simpler for you.

    The main thing is to make sure the pipe is cut square, as you would with copper anyway, but the inserts need to go in nice and neat, other than that, just the usual precautions of compression joints
  3. Pollowick

    Pollowick Well-Known Member

    As with Craig's comments and add that you should ensure the cut is CLEAN - do not use a hack saw or Stanley knife, a proper cutter is the best way.

    AND make sure the olive is copper not brass. They deform/mould to shape a lot easier and the plastic fitting manufacturers recommend them.
  4. retiredsparks

    retiredsparks Well-Known Member

    Buy a pipe cutter.
    Keep pipe protected before use.
    use solid inserts for compression fittings
    use copper ...not brass olives
    dont overtighten
    straight lengths of plastic pipe are fine...for stubs.
    ensure full insertion into plastic fitting...the marks on the pipe will help with this
    see JG webbsite for installation advice video
  5. retiredsparks

    retiredsparks Well-Known Member

    Pollow...i see you "arrived early" as usual...:D
  6. Stan Lee Blade

    Stan Lee Blade Active Member

    Thanks for that: I am retired now and have to admit I am really old school. I could still actually wipe a and roll a lead pipe joint but Speedfit is all new to me.
    I have to admit when with blowlamp all fired up and looking down at the plastic pipe my first thoughts were shi,,,,,,,,,,,,,,,t
  7. Stan Lee Blade

    Stan Lee Blade Active Member

    Thanks for the advice : The inserts the plumbing centre sold us for the Speedfit pipe are plastic with rubber olives at both ends ( section that goes in pipe and the larger end that goes into the compression fitting . Have got a cutter and I have some copper olives.
  8. Stan Lee Blade

    Stan Lee Blade Active Member

    Sorry meant to say o rings on the inserts ( not olives )
  9. Stan Lee Blade

    Stan Lee Blade Active Member

    Thanks everyone for the advice. I would say this plastic pipe must be a lot easier to install under flooring less boards and traps cut, with less connections and 90% bends at every corner.
  10. DIYDave.

    DIYDave. Well-Known Member

    All fine mixing copper, compression and push fits all on one system, as long as correct prep and methods are used - as with all tasks

    Your gonna get negative comments about using plastic and statements that only copper is a ‘proper job’ but, uv already got a part plastic system so add away - millions of houses are plumbed like this or part copper/part placky and I’m sure they haven’t all floated away :)

    Usual to run tails in copper as your right, plastic to rad valves looks poor

    I’m only diy but I would say;

    Always cut plastic pipe neat, clean, straight. Plastic pipe slice great here or a ratchet type, both give a nice cut, no burrs. Hacksaw will do but not preferred method, harder to cut straight and need to remove burrs

    Always use same make inserts as pipe (and fittings if using push fit) won’t make a difference though what copper compression you use

    So, nice clean cut pipe, slide on compression nut, followed by olive, pop in insert. Can give the olive a wipe of sealing paste, LSX, Fernox Jointing Compound, Tru-Blu (choice is yours) not totally essential but for us diy’ers, gives a bit more confidence (I like Tru-Blu myself)

    Offer pipe up to T, fully inserted, hand tighten nut. Not necessary to wrap threads on compression fittings with lashings of PTFE - this is always a sign of a nervous diy’er :eek:

    It’s the olive that seals pipe and fitting. If you have water leaking past the olive, wrapping threads with tape is a short term bodge - you really don’t want this under floorboards waiting to go wrong

    Now the tricky part (for us diy’ers) Just how tight do you crank up the compression nut ?

    Well, it’s a feeling kinda thing, gained from experience. You can actually get a compression fitting water tight just by hand tightening your nuts ;)and getting the olives to bite - simple but amazing piece of engineering (but don’t axtually leave the fitting hand tight, this is more an experiment type of thing)

    Often leaky fittings are caused by over tightening. This causes the olive to compress too much and partially crush the pipe (copper or plastic) Water then gets under the olive and you have a leak

    Hold the Compresion fitting with grips or adjustables (some have a flat section for this purpose)
    So hand tight, then 3/4 to 1 full turn with 2nd pair grips. This is clearly approx as how tight is hand tight exactly ? Water test before fitting back floorboards, can always nip up a little tighter if needed - just don’t go at all with all guns blazing and ‘wring its neck’, you will knacker the poly pipe and insert - good luck and enjoy :)
  11. DIYDave.

    DIYDave. Well-Known Member

    Pretty sure inserts with O Rings (super seal) are not to be used with compresion fittings - this type is for fully plastic installation, ie push fit / speed fit fittings

    Don’t use these inserts with copper compresion - plain inserts (plastic or stainless steel only)
    retiredsparks likes this.
  12. CGN

    CGN Well-Known Member

    As Dave said above, just plain inserts for compression fittings.

    There are no advantages to using compression tees, so I would swap them for push fit and make life even easier and potentially drier :)
  13. Stan Lee Blade

    Stan Lee Blade Active Member

    I’m glad I posted this for advice. I have been given the wrong inserts for compression ( super seal ) i can get the correct ones from screwfix .. but then again I might just ( as you say ) use the push on Speedfit Fitting to tee into the pipe
    If I do this does the 15mm copper pipe just push into this fitting ?
  14. WillyEckerslike

    WillyEckerslike Well-Known Member

    Yes. As with the plastic make sure there are no burrs on the copper - cutting with a pipe slice will ensure that. You don't need inserts with copper - sorry if that's too obvious.
  15. Stan Lee Blade

    Stan Lee Blade Active Member

    ok thanks and no problem : all good advice
  16. WillyEckerslike

    WillyEckerslike Well-Known Member

    Just make sure you have pushed the pipe fully home (plastic or copper) - can be misjudged on the first few. Make a pencil mark on the pipe at the approx depth you think the pipe should insert to then you will know it's fully seated - it will be visually obvious if it hasn't although it may feel like it has.
  17. Doall

    Doall Active Member

    I learnt the hard way as had a fitting blow due to using wrong insert and had to go through public liability. Now I never use compression fitting on plastic, always use a straight coupler and then change to copper.
  18. retiredsparks

    retiredsparks Well-Known Member

    Wiily as i mentioned earlier...solid inserts..(no O Rings) and the pex pipe has marking on it...so that you cut on one marking and push till you get two marking deep.
    Plumbers forum...and plumbers merchants ......pmsl... and I am just sparks.
  19. retiredsparks

    retiredsparks Well-Known Member

    Lee you have to use a fluffy flame on PEX pipe....dont overheat it.....otherwise the joint will leak.:p
    You def am old school and it is often difficult to trust new stuff...but.....read the manufacturers blurb and follow it..and the results are within spec.
    Most problems on modern stuff is cause by unskilled untrained numpties..and DIYers who use the product outside the specs.
    Example, push fit stuff is guaranteed for 25 generally..... failures being due to incorrect installation and lack of attention to good practice.
    Stan Lee Blade likes this.
  20. Stan Lee Blade

    Stan Lee Blade Active Member

    Fluffy flame you say and there was I blaming it all on lead free solder .
    WillyEckerslike likes this.

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