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Discuss wet underfloor heating problem in the Underfloor Heating Forum area at UKPlumbersForums.co.uk.

  1. homemaintenance

    homemaintenance New Member

    Can anyone help,Have had to renovate part of an underfloor heating system in a barn conversion which is approx 15 year old.the original system manifolds were leaking and corroded and the control system was seized and u/s.the original system was for most part UPonor so i replaced the manifolds with same manufacturer but the pipework had to be adapted as originally it was 19mm so had to adapt to 20mm,i also fitted a new thermostatic mixer valve and ups 15/80 circulating pump,all pipework was in 28mm copper.The problem i have is that i cannot get system to circulate,all the flow pipework is hot including manifolds but the return is cold and stays that way,i have flushed the system several times and bled all all air out of system,have checked several times but still no luck,according to the flow gauges there is no flow but have tried to find out why but cannot find a reason.
    The original system was installed with no isolating valves whatsoever,the old part of system not changed still has no isolating valves,i have fitted valves to the new part.
    Has anyone got any suggestions as to why i cannot get a flow reading or why i cannot get return working.
    • Like Like x 1
  2. bogrodder

    bogrodder GSR

    Put up some pictures so we can have a gleg.
  3. Uheat – Wojtek

    Uheat – Wojtek Sponsor

    Hi there,

    Can you please send some pictures?
    Have you replace the old manifolds with new Uponor ones with V5 control pack?
    If so I would like to see the connections (flow and return) as this system works on opposite way as majority of other UFH systems. flow is being connected to the return part of the manifold.

    I'll be happy to help once see the photos.

    Many thanks
  4. homemaintenance

    homemaintenance New Member

    Hi There have attached photos(hopefully) for your info,Is this enough?I have just replaced the existing manifolds with V5 type not control pack.
    IMAG0267.jpg IMAG0268.jpg IMAG0269.jpg IMAG0263.jpg
    Many thanks for any help.
  5. Uheat – Wojtek

    Uheat – Wojtek Sponsor

    Hi there,

    many thanks for the photos, looks like a nice installation job.

    Can you call me on 01394 593 304 so we can check few things over the phone?
    I I won't be able to help I'll give you a number to Uponor technical support and perhaps they will help.

    Many thanks,
  6. Uheat – Wojtek

    Uheat – Wojtek Sponsor

    I'm looking at the photos again and I need to ask you a silly question (sorry) - photo No 1 - is the pump pumping the water into the right direction?
    You have got a mixing valve flow and then pump. I've got a Grundfos pump in my hand right now with motor in the same position as the one on the photo and the arrow on mine would indicate that water is pumped back to the mixing valve.
    I'm sorry if I'm totally wrong but I thought to ask.

    Many thanks,