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Hvac calculation

  1. May 23, 2010 #1
    Dear all
    I am working in MEP field but no experience so I need your helps how find out an area cfm calculation and what is the ton of Ac given, what is the power how to find this calculation ..
    BTU/HR - British Thermal Unit /Hr.

    CFM - Cubic Feet per Minite

    TMBH - ?

    SMBH - ?

    what is mean by TMBH and SMBH ?
  2. jcsd
  3. May 23, 2010 #2


    User Avatar

    Staff: Mentor

    Welcome to PF.

    If you're working in the HVAC field, don't you have a more experienced engineer to mentor you? There is no other effective way to become an HVAC engineer. Anyway....

    The capacity required (CFM at a certain temperature) is usually calculated using software for the internal and skin (walls, windows) load and fraction of fresh air and its temperature. Unless it is 100% outside air and a high volume (like for a lab), then it is just calculated using a psychrometric chart.

    A ton of cooling is 12,000 BTU/hr

    TMBH is total MBH (MBH is 1000 BTU/hr)
    SMBH is sensible MBH (the part of the capacity related to temperature change, not condensation of water.
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