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Discuss Low flow rate in outside and mains cold tap only. Mains pressure combi system in the Fittings & Pipes area at UKPlumbersForums.co.uk.

  1. JVog

    JVog New Member


    We have been in our house for just over two years, we have always had low pressure in our downstairs cold tap (mixer tap), hot is fine, and also in our outside tap, this branches off the main cold line before it hits the cold side of the tap. (please see images, cold is the right side pipe).

    We have had united utilities out and they have said the pressure in the street is fine and also, the pressure in our downstairs bathroom taps, electric shower, dishwasher and washing machine all working fine.

    They advised me that it is the flow and not the pressure, i have my suspicion that the lime in the old plaster has corroded the pipe so i started chasing this out but i feel i could go on forever with no result, also a suspicion is the fitting penetrating the pipe to channel water to the outside tap, does anyone have any similar issues and/or experiences with this? any help would be much appreciated. I have attached image that shows the pipe going into the lime plaster and also the fitting to the outside tap.

    Thank you.

    pipe 3.jpg pipe.jpg pipe2.jpg
  2. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    The outside tap fitting on your pipework is cheap DIY tat and is not fit for purpose nor does it meet water regs. It cuts a piercing point into your pipe there is every possibility that this metal remains in the pipework partially blocking it. My advice would be to cut that section out and re-pipe completely with the correct isolation valve and check valves
    • Agree Agree x 4
    • Like Like x 2
  3. WC1

    WC1 Active Member

    Outside tap fitting looks to have a few wraps of self amalgamation tape preventing a leak / flood. Get rid quick .
    Check your flow rate by timing discharge of a known volume. Get a pressure gauge to check pressure. Pressure and flow are different but low pressure and low flow generally look the same. You need to know which problem you have.
    • Like Like x 2
  4. JVog

    JVog New Member

    Hi guys,

    Thank you for your quick replys, the pressure is fine elsewhere in the house and all mains fed so it is the flow that is the issue, it is more than likely the fitting to take the water to the outside tap, i will re pipe with a copper tee fitting and new tap,

    Thank you again.
    • Like Like x 1
    • Winner Winner x 1
  5. Coby kenny AGUILAR

    Coby kenny AGUILAR Member

    What condition are the taps in?
  6. JVog

    JVog New Member


    Thanks for your reply.

    Both inside and outside taps are in good condition, although cheap, i also find it too coincidental that they are the only two taps in the house that have low flow and it not being an issue in the line?

    Do you think it could be something else?

  7. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    Post #2? Did you not read them all
    • Funny Funny x 2
    • Like Like x 1
  8. Rytis

    Rytis New Member

    Hi. Taps cartrige might be scaled up or rubber gone. And yes that quick connection for outside tap is no good for flow too ;) good luck
  9. Rytis

    Rytis New Member

    Send tap pic too :)
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