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New Glow Worm Combi Low Flow Rate

Discussion in 'Plumbing and Central Heating' started by rideforever, 5 Jun 2020.

  1. bernardgreen

    bernardgreen

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    In this boiler's technical data there are "specific" flow rates listed.

    All these "specific" flow rates are greater than the flow that the flow rate limiter will allow.

    Perhaps "specific" has a special meaning.
     

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  3. rideforever

    rideforever

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    Blimey, need to get Poirot on the case of this incomprehensible EU-designed boiler; it needs a good sorting out.
     
  4. lightning

    lightning

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    City plumbing only do the ultimate with 10 years warranty
    Have fitted loads and no one has ever complained of the flow rate
     
  5. rideforever

    rideforever

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    They seem to also do some with a 5 year warranty actually.
    Problem is they specify on their website a flow rate of 12.4, when it is actually 10.
    That is just a small problem eh !!!
    Maybe instead of 30kw it's actually 25kw too.
    They also specify the width, but maybe instead of 300mm it's 350mm.
    Ha. Comedy.
    You would think that mis-advertising the specifications would be illegal or something.
    Mr Barnier has a lot to answer for, maybe he's really in charge of the whole thing.
     
    Last edited: 15 Jun 2020
  6. denso13

    denso13

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    Have you asked Glow Worm about it yet?
     
  7. rideforever

    rideforever

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    The installer did last week and they said not to touch the machine.
    But, Vaillant said that to me last time ... they said no dice; but once I sent the claim into Small Claims I got a full refund in 10 days - they were the subcontractor with SSE, that was a claim about a boiler maintenance contract. People on the helpdesk are not equipped to make any decisions. Meanwhile I'm getting a new shower head and pondering all the advice here.
     
    Last edited: 15 Jun 2020
  8. ScottishGasMan

    ScottishGasMan

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    The energy, betacoms and ultimates all have restricters, like most modern combis. And yes, they are all 8/10/12litre restricters depending on boiler size.

    Now where you say they advertise 12l/min, they do not. You just don't know how to read a technical manual. They are required to state a flow rate at 35 degree rise, its not a statement of what the flow rate is, flow rate will be dependant on a number of factors, plenty boilers are fitted on supplies that cant flow enough water to reach the full flow for example. The manual states what restricter is fitted, its the person who specifies the boilers job to arrange and fit one to whatever spec they have agreed with you.
     
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  9. ScottishGasMan

    ScottishGasMan

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    Also, I would advise your installer to speak to his local rep, I'm quite sure they could get exemption on removing the restrictor for warranty if that is your concern, as removing it wouldnt affect the operation of the appliance other than to lower the outlet temperature.
     
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  11. rideforever

    rideforever

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    Okay, the manuals for the Energy, Betacom, Store don't seem to mention a restrictor - I checked all the pdfs this morning. Perhaps you can point out where they mention the restrictor?

    So you are saying that under certain conditions this boiler that has a 10l/min restrictor on it .. it would actually produce 12.4l/min? In which case I would only ask firstly why my boiler is producing exactly 10l/min, and secondly why the equipment is called a 10l/min restrictor?

    The several installers I saw all use the value of the 35c rise, and compare it to the existing delivery at the taps. Are they all wrong then? What should they be doing in your opinioning, quantum analysis on the metallurgy of the inner workings of each boiler?

    The manufacturer on the website compares boilers on their specs, include the 35C rise. What would be the point of that if the effective flow rate could be any other number depending on whatever other limiting factor there is ... in the machine itself.

    Do you not think that the installer, vendor and public ... that their priority is to know what amount of hotwater they will get ... or do you think they don't really care ?
     
    Last edited: 15 Jun 2020
  12. denso13

    denso13

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    Read EN 13203, it explains how manufacturers are required to describe hot water outputs.
     
  13. ScottishGasMan

    ScottishGasMan

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    No Unless your water pressure is unusually high a 10l/min restrictor will only allow 10l/min. They have to state what flow rate would give 35 degree rise in temperature from the cold going into the boiler and the hot going out, it has zero correlation to the actual flow you get from a boiler, its a technical document that must include this information.
     
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  14. ScottishGasMan

    ScottishGasMan

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    1.JPG 11.JPG 111.JPG

    All taken out the technical data tables in the manuals currently on the glowworm website
     
  15. lightning

    lightning

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    What I was saying that the ultimate 3 is exclusive to city plumbing yes 5 and 10 year warranties.
     
  16. Gasguru

    Gasguru

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    https://www.glow-worm.co.uk/homeowner/products/ultimate-combi-boilers-1473.html#specification

    Misleading? I think so. No doubt somewhere in the approvals there's a reason for fitting a 10 litre/min flow limiter but to publish the 12.4 litre/min figure knowing it's unachievable and not saying so is incompetent.

    Under the type approval the specific flowrate at delta 35 must be given....and over the years that flowrate has become a benchmark standard for installers and the public to compare performance. In fact many manufacturers will actually state that flowrate is achievable.

    Something has changed, I've looked through several boiler specs from many years ago, as an example I looked at 24kW boilers that typically quote 9.5 litre/min at delta 35 and they are sensibly fitted with a 10litre/min restrictor.
     
  17. rideforever

    rideforever

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    Thanks for your help
     
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