Questions for choosing HVAC plants and Fan capacity.

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Hi, everyone: This is my first baseline model, and this simple model is only purpose for my training . The building is a 6 floors office, and the HVAC system is VAV with PFP box as the baseline required. After I completed the Building Shell & Internal Loads steps, I made a run and got the Space Peak Loads Summary like the illustration below. I want use them to choosing the reference plants Capacities ,the Space Flow Rate and the Fan power. And there is 3 questions: 1. You can see there is a Space named "Plum", the unconditioned space above the ceiling. Should we calculate the plum loads when we choose the VAV system and Fan plants? Should we direct use the building peak load for choosing the chiller's capacity? 2. ASHRAE 90.1 appendix G 3.1.2.2 said that the Equipment Capacities should be oversized 1.15 for cooling and 1.25 for heating. Is this suggestion suit the calculation way which I used? My friend told me he always choose 70% of the peak loads for the plant capacity(but he use TRANSYS, not eQUEST), is that a good method ? 3. Using the appendix G 3.1.2.9 method , we could calculate the P-fan( watts ). But I found I could only input "in. WG" & CFM in eQUEST, there is no way to input the P-fan. It's really puzzled me. By the way , is there any simple method for make a baseline? We need to simulation 4 directions ,and if there is a lot of spaces in the model , it should be really a great amount of work to do(like specify the air flow rate of every space's parallel fan). That's all. thank you very much, any tips should be appreciate. Best wishes. Joey ------------------------------------------------------------------------ --- Joey Jiao Graduate Engineer
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