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-   -   Pump head calculation formula (https://www.askmehelpdesk.com/showthread.php?t=313776)

  • Feb 6, 2009, 02:36 AM
    engineer safdar
    Pump head calculation farmaula
    Send & explaine me pump head calculation farmaula
  • Feb 11, 2009, 02:20 AM
    Ashnotcon

    Safdar,Your question is not explicit. You need to state what purpose you are applying the pump to serve. Is it a booster pump? Or a chilled water pump for HVAC?
    The way we calculate the head for a chilled water pump in a closed system defers from the way we calculate for a booster pump in plumbing.
  • Mar 16, 2009, 05:17 AM
    Quantum
    The way to calculate pump heat:

    In closed system: you add the pressure losses due to piping and all accessories with the piping such as elbows, valves, strainers etc. plus the pressure losses due to equipments
    In short the pressure losses in the longest run of pipes in series with the piping.

    In open system: same as the above plus residual pressure for the furthest fixure and cooling tower height difference (if any)
  • Jun 7, 2009, 02:34 AM
    1099
    In a closed circuit is it necessary to calculate the losses in yhe chilled water return lines.

    Regards 1099
  • Jun 7, 2009, 02:41 AM
    1099
    Is it necessary to add up the friction losses in a return line of a closed circuit chilled water line?



    Regards 1099
  • Jun 7, 2009, 02:44 AM
    1099
    Is it necessay to add up friction losses of water return lines in a closed chilled wter circuit?
  • Jun 11, 2009, 03:14 AM
    ashiskg

    In a chilled water secondary system which has no of FCUs & AHUs do you have to consider pressure drop through the cooling coils of all the units?
  • Jun 19, 2009, 04:49 AM
    Ashnotcon
    1099,
    In a closed system, it is important that you add up all frictional losses due to pipe and fittings along return line while calcuting your pump head. Remember it is a closed system and the pump would have to push the chilled water through both supply and return lines, thus it must be able to overcome the frictional losses generated by their pipes,fittings and even the coil.

    Ashiskg,
    In a chilled water secondary system you must consider the pressure losses through the cooling coil of the AHUs and FCUs. Apparently, the cooling coils would pose some resistance to the flow of chilled water and this MUST be overcome by the pump head.
  • Jun 19, 2009, 04:59 AM
    Ashnotcon

    During load estimation for an office block with indoor transformer and electrical panel rooms to be cooled, how can I get an idea of the heat dissipation from the equipments when it is not stated in their literature? Is there a guide from ASHRAE for these,as in, kw/sqm ?
  • Jun 30, 2009, 01:36 AM
    JAMAL ISMAIL
    What is the function of the pressurization unit in chilled water system
  • Jul 16, 2009, 12:48 AM
    omer86
    The pressurisation unit provides make up water in the chilled water pipes there is considerable loss of water while the pump are out operation and which it starts working there should be no losses in pressure for which it maintains the correct water level
  • Aug 6, 2009, 04:41 AM
    Quantum
    Hello All

    1099: correct you have to count the return. It a loop.

    Ashisskg: No, only one unit will be added to the friction, the unit that is in the longest loop

    Ashnotcon: Transformer heat dissipation is 1.5% it's size in KW. Electrical Panel is 1.2% of its size in KW.

    Omar: pressurization unit is used to cushion the expanded water in the pipes, so pipes do not burst. It also used to compensate pressure and add water to the system if the pressure in the system drops due to leaks or water getting colder.


    Please rate me
  • Sep 6, 2012, 11:05 PM
    shaikh anwar
    I need to calculate booster pump head for water supply
  • Sep 6, 2012, 11:06 PM
    shaikh anwar
    I want to calculate booster pump head for water supply

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