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[EnergyPlus_Support] Breakdown of loads

Hi everybody,
   
  I am modelling some buildings here using the Purchased Air object and I am interested in evaluating cooling demands. 
  
I want to plot air load breakdowns and inside surface load breakdowns to understand better the loads on my AC system and on my building envelope respectively. As Energy Plus uses the heat balance method I assume that I can get the breakdowns I want as follows:
   
  1) Air load breakdowns:
   
  Zone/sys sensible heating and cooling energy = (zone convective loads from surfaces) + (zone total internal convective heat gains) + (zone infiltration sensible heat gains and losses) + (zone ventilation sensible heat gains and losses)
   
  From this equation the only variable I cannot get directly form EPlus is the "zone convective loads from surfaces". I could notice that this can be plotted per surface but not for the whole zone, so I was thinking about getting it from the above equation by subtracting the internal convective gains and the infiltration and ventilation gains and losses from the sensible heating and cooling energy, would that be ok? Or I missed some variables in this equation?
   
  2) Inside surface load breakdowns:
   
  Opaque surface inside face conduction gains and losses = (zone convective loads from surfaces) + (zone total internal radiant heat gains) + (zone total internal visible heat gains) + (zone windows heat gains and losses) + (zone radiant exchanges with other surfaces) 
   
  I could get the "zone convective loads from surfaces" from the equation above and figure out the "zone radiant exchanges with other surfaces" in this equation. Would that be a correct breakdown of loads to evaluate what is going on in the inside face of the zone surfaces? Or did I miss some variables in the equation and/or misinterpreted the meaning of some of them?  I am not quite sure if the windows heat gains and losses apply directly to this equation of if I shouldn't be considering only the portion of transmitted solar radiation as the rest might be embedd in some of the other variables.
   
  I thank you very much again for your attention 
   
  Best regards,
   
  Clarice

  P.S. Mike loads of thanks for the last reply
   
   

 		
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