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Recent content by Clunsy

  1. Clunsy

    DHW Cylinder

    Well spotted. The 145kW was from you original calc. I feel like ive learned a fair bit from this conversation, so thanks again.
  2. Clunsy

    DHW Cylinder

    Perhaps its not the most scentific way to approach it, but ive got the value of 5degC loss/hour from the assumption that it would take a similar cylinder around 8 hours to cool from 60 to 20degC. On reflection, perhaps it would be closer to 10 or 12 hours, but i dont think we're far away. That...
  3. Clunsy

    DHW Cylinder

    I totally agree that those factors would be required for an exact answer, but for the time being would you agree that 5degC per hour would be a fairly standard loss from a tank that size, with average quality insulation?
  4. Clunsy

    DHW Cylinder

    The boiler is 560kW. The cylinder is only a very small part of its load. With standard (not great) insulation would it be fair, roughly speaking, to assume losses of around 5 degC/hour? If i understand your worked example the total heat required to heat the cylinder from 20 to 100 degC is...
  5. Clunsy

    DHW Cylinder

    If controled right, thats how it should work - cut in (say 55 degC), cut out (say 65 degC). But as the primary pump is currently left on manual and the cylinder valve is manually open, the cylinder is never cooling below the boiler flow temperature (around 80 degC). Effectively im trying to...
  6. Clunsy

    DHW Cylinder

    2 values im not sure of are the size of the primary pipework and the size of the primary pump (possibly around 2kW?). For the purpose of the exercise im happy to use estimates for these. Again, thanks.
  7. Clunsy

    DHW Cylinder

    Thanks very much for your responce Desertfox. The heat source is a 560kW gas boiler, via a primary pump. As well as the DHW cylinder, it is also serving the building's radiator circuits, AHU's and a large heat exchanger for the plant's process. From an efficency point of view, i believe the...
  8. Clunsy

    DHW Cylinder

    Hi All. The following query may seem fairly basic for you mechanical guys, but please forgive me - im electrical! Im currently assessing the need for a DHW Cylinder in an industrial plant. The cylinder is 2m x 1m, so i've calculated the volume to be 1570 litres. As the diverting valve is...

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