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At the end of the CH FLow

Discussion in 'Plumbing and Central Heating' started by WabbitPoo, 15 Sep 2021.

  1. WabbitPoo

    WabbitPoo

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    Sorry if this is a thick question: I presume the end point of the CH flow pipe (the furthest point from the combi) is connected directly to the end of the return pipe? If so is this why I have a small radiator installed where the old hot tank was: to allow the system to still flow correctly (plus it acts as an airing cupboard I guess)

    The grey things on this rad (pictured) are just an easy way of splitting the flow off to another rad? This cupboard is going soon, so this rad will go with it.

    IMG_20210914_145047.jpg
     
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  3. Elkato531

    Elkato531

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    The flow and return pipes are not connected. The water has to pass through a radiator to get back to the boiler. If the radiators all have TRVs there is a possibility that they will all close and that's why a bypass valve should be fitted. The bypass valve may be an integral part of the boiler or could be an external component on the system pipework.

    As far as your photo is concerned, the grey parts are manifolds which allow separate flow and return connections to several different radiators. Its a bit untidy but if its in an airing cupboard, at least its out of sight. Not so good though are the iso valves just before the manifolds. They are not designed for heating systems and are guaranteed to leak eventually. They are also quite restrictive and as it looks like the flow for three radiators passes through them you may have problems with those radiators not heating correctly.
     
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  4. WabbitPoo

    WabbitPoo

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    Thanks. This whole assembly is going. Might the rad have been fitted as a means of BEING the bypass valve? Or can I just remove it, connecting those spurs in some other way?
     
  5. oldbutnotdead

    oldbutnotdead

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    Yes it might have been (usual sign is no TRV). Not permitted nowadays. That manifold setup is fugly...if every other rad on the system has TRVs fitted, the boiler requires a bypass & there isn't one somewhere else then replace that rad with a bypass valve (or link flow & return with a bypass valve somewhere else)
     
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  6. dilalio

    dilalio

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    That is a bona-fide lash up!
    Get that ballofix isolator (and any others) removed from the CH circuit.
     
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  8. WabbitPoo

    WabbitPoo

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    lol I agree its a mess - not guilty.

    We have a towel radiator in the bathroom which has no TRV on it and is never closed off, so won't that do as a means of ensuring the system flows?
     
    Last edited: 16 Sep 2021
  9. oldbutnotdead

    oldbutnotdead

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    Yes it would do, but for £20 in bits and half an hour's work you could do the job properly. You can keep your towel rail in place as is if it suits you, the bypass will only operate if flow pressure exceeds return pressure by whatever pressure you set the valve at. Which won't happen if 1 or more radiators are operating...
     
  10. WabbitPoo

    WabbitPoo

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    Thanks. Might the combi have one "internally" as it were....its a worcester bosch greenstar HE (an HE 30 if memory serves, though I'm not there right now)
     
  11. oldbutnotdead

    oldbutnotdead

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  12. WabbitPoo

    WabbitPoo

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    I can see no mention of a requirement in the installer's guide, but I'll get one fitted anyway when I can. Thanks
     
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