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How to sell a boiler II

Discussion in 'Plumbing and Central Heating' started by vulcancontinental, 6 Jun 2017.

  1. AGAS

    AGAS

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    You will find he is just relaying cr@p from his pen friends so we will have to wait for the next first class service from the post office to get more sense about boiler testing from old berny :)
     
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  3. bernardgreen

    bernardgreen

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    Total heat output = total heat input = useful heat + wasted heat
    Efficiency shown as a percentage is ( useful heat / total heat input ) x 100
    That is the absolute efficiency of the appliance, it can never exceed 100%

    if that 100% was the absolute efficiency then the appliance was pefect and could not be improved.

    you cannot improve an appliance that is already perfect in terms of efficiency in converting fuel into useful heat

    Redefine the test, how, the basic test is to measure how much heat is transfered compared to how much heat was produced by the combustion of the fuel. How can that be redefined.

    A boiler with the best available performance may have an absolute efficiency of 50% but be performance rated as 100% because with the technology available the useful heat output is 100% of what can be achieved. Test results will show 50% efficiency. Developing technology may result in a new design that has an absolute effciency of 75%. What performance percentage does that imply ? One could "translate" using the same factor of double ( performance / absolute ) and get 150%.
     
  4. Dan Robinson

    Dan Robinson

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    Speculation and hearsay. You have no idea what the test was.

    You have not explained how the test house (NOT the manufacturer) has come to the results.

    It is THE TEST HOUSE that have put 122% on the certificate; so there is nothing fraudulent about it.
     
  5. bernardgreen

    bernardgreen

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    I am posting my own opinions which are based on A level physics from the 1960's and experience and knowledge gained over many years.
     
  6. Dan Robinson

    Dan Robinson

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    So did you do boiler and PFHR testing in 1960's A levels?
     
  7. bernardgreen

    bernardgreen

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    So this supposedly reputable and independent TEST HOUSE is happy to produce and publish results which defy the laws of science.

    Or have they been very careful to say that this 122% efficiency is a performance value produced by comparing the test sample's absolute efficiency with the absolute effciency of a less efficient boiler that has been tested previously.
     
  8. Dan Robinson

    Dan Robinson

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    There is no mention of performance on the certificate.

    So your A levels did not include PFHR, boilers or stack losses when you sat them 70 years ago? And you don't think senility could be playing a part anywhere? ;).
     
  9. bernardgreen

    bernardgreen

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    2017- 70 = 1947 and not 1960's, being good at maths and getting accurate (valid) results is important when calculating boiler efficiency.

    One experiment we did ( even before O levels ) was to determine the calorific value of methylated spirit by heating a known volume of water so it was a very practical education.

    My experience with monitoring systems for industrial boilers came some years after the A levels.
     
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  11. Agile

    Agile

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    That implies that you will accept that a boiler can be more than 100% efficient at recovering the heat available from the fuel?

    But presumably these test houses are rather silent at exactly how their 122% is defined !

    Unless they can bend the laws of physics which we live with.

    Cue for ChrisR to explain black holes and other exceptions!
     
  12. Dan Robinson

    Dan Robinson

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    But again.... It depends on what the test was and when it was defined.
     
  13. Dan Robinson

    Dan Robinson

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    ****************
     
    Last edited by a moderator: 1 Aug 2017
  14. Did not think Google has been around that long :mrgreen:
     
  15. Agile

    Agile

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    I am surprised that all the boiler makers don't go to that Test House so they can also "achieve" these magical efficiency figures!

    Double Dutch comes to mind!
     
  16. Maybe they buy second hand test equipment from a leading car manufacture,
     
    Last edited by a moderator: 1 Aug 2017
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  17. Agile

    Agile

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    Are you thinking of Volkswaggon?
     
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