Appendix G VAV Box Type

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His logic is based on using the same/similar VAV box control logic between the Baseline and Proposed. which is a viable argument, especially since Appendix G is not explicit. So its a support by omission...? coworker here had a great point in that a Parallel Box by nature is typically a Dual Max Single Min, since the Fan would increase the airflow in heating. Though, this depends if one is looking at airflow from the Damper Point of view or the Box Point of View. If looking from main damper, its still a single max single min; from a box airflow is it dual max single min.

rechecking the PNNL guide, for PFB 3.5.5.2; it calls out single max single min; but the verbiage is written from primary damper point of view.

For VAV with reheat terminals the 90.1 PRM does explicitly state requirements for minimum and maximum flow rates (single min and max) but not in between.

PRM G3.1.3.13 and G3.1.3.14 contain requirements related to VAV Box Minimums (Sys 5/7) and FPB Fan air flows and airflow minimums (Sys 6/8) respectfully. Is that what you were referencing @MatthewSteen ?

Knowing the min setpoint(s) does not define the controls logic; thus the question. The absence of a 'heating maximum xx%' requirements implies a Single Max/Single Min control of the Primary damper; but that is support by omission not explicit wording. Its possible (Baseline Htg Max) = (Proposed Htg max) and still comply with min %s; making it reverse return. Not a fan of that tho...