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  1. Sofasurfer7

    Sofasurfer7 New Member


    Currently we've got a vented system in our 2 bed 1 bathroom 1st floor flat, which doesn't produce much flow for our mixer tap shower. I've decided to seek out getting a unvented direct cylinder fitted (electric only property). I've got three quotes and am in a quandary which one to go further with.

    A: 800 for a everflo 120L. (Was 879 for baxi) Stay with current piping to stop cock (unsure of width), as advised that 22mm from sc to cylinder won't make much difference but will do work if asked to. Would run pipes through loft. External relief valve.

    B:1050 for 22mm back to sc. fitting of Joule 120L cylinder. 22mm to run on grfloor through bathroom. Did say possible tundish inside. No drain outside interestingly. I asked if we could go for a cheaper cylinder and was advised that cheaper ones have glass interiors (wasn't aware of this).

    The third quote is similar to B (980) without 22mm but haven't called for spec on cylinder as comms have been a bit crap and bloke didn't seem too bothered when coming round to do the quote.

    I'm unsure what's best. All three have advised that it's not going to be like a power shower but it'll give an improvement to what's there ATM (which is fairly poor). If 22ml doesn't make much difference is it worth it? I've read otherwise on the internet.

    Also I haven't had a pressure reading done although A is willing to come round and do that. My feeling is there is enough pressure and flow but it's at the bottom end of acceptable.

    Please help.

  2. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    I would bin all of them if they haven't been round / tested the pressure or flow

    Make sure who ever you get is G3 registered
  3. gmartine

    gmartine GSR

    Just fit a shower pump that'll make use of your hot water store and give you plenty of pressure at the mixer.
    • Like Like x 1
  4. Sofasurfer7

    Sofasurfer7 New Member

    They've turned the cold tap on which comes off the main, but not put a gauge across it
  5. bambers

    bambers GSR

    Most unvented manufacturers will specify min 22mm mains with flow of 20l/min 3 bar pressure get it tested before changing over or you will be wasting your money a good plumber should be able to advise on the correct solution.
    • Like Like x 1
  6. galaxy_plumbing

    galaxy_plumbing Plumber GSR

    Needs flow and dynamic pressure measure then you can look for options. Where is your cold water tank located?
  7. Sofasurfer7

    Sofasurfer7 New Member

    In the loft, probably about 3 meters off floor level (from the floor of the flat, not the loft)
  8. galaxy_plumbing

    galaxy_plumbing Plumber GSR

    Perhaps fitting pump as suggested would be a better solution.
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