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Discuss which to use, 10mm or 15mm pipe? in the Plumbing Forum area at UKPlumbersForums.co.uk.

  1. Serval

    Serval Member

    As per the attached pic, Im planning to run two radiator pipes inside a chase that ivew made in a partition wall so that the pipe work will all be hidden once ive finished the bathroom.

    The old pipe work is 10mm microbore with 15mm adapters and a short section of 15mm where the pipes came out from the old paneling.


    i was going to cut the old pipe work somewhere on the straight section along the back wall somewhere before the bend and solder in the new pipe work

    Would you guys join in a new section of 10mm that could be easily bent/shaped to fit into the chase and solder on short section of 15mm near the end that will fit the rad?

    or would you just cut and join in 15mm pipe all the way?

    just after some opinions of the best approach for this one

  2. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    How big is the rad ?
  3. Harvest Fields

    Harvest Fields S. Mod Trusted Plumber GSR Top Contributor!!

    As above. If you are running 2 rads from one flow and return. I would want 15mm pipework all the way.
    • Like Like x 1
  4. Serval

    Serval Member

    Its a small towel rail. 400mm wide by 800 high.
    Will only be running this rad off the pipe work in question.
  5. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    10mm is fine then
    • Like Like x 1
    • Agree Agree x 1
  6. Serval

    Serval Member

    Cool, cheers
  7. Rob Foster

    Rob Foster Top Contributor!!

    That will be fine towel rads only provide candle heat and are covered most of the time anyway. centralheatking
    get a mini bender and go,for it
  8. Warmiger

    Warmiger New Member

    I will always use 15mm pipe. I have to power flush heating and micro bore is to easy to clog up in my opinion.
    Maybe it’s just me being old school
  9. Rob Foster

    Rob Foster Top Contributor!!

    Some say that the smaller bore pipe properly installed on the end of a large bore circuit
    22mm..2 15mm...2 10mm results in much higher liquid velocity and greater scour.
    We were mucking about with pump cavitation years ago and this popped up as a side show.
    Rob Foster aka centralheatking
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