Our design has four Dual Duct VAV units that share common plenum return that is recirculated thru both hot and cold deck of each unit. Each unit has it's own OA intake. We've done separate calcs for each unit w/ zones associated to each unit. The reviewer had stated that the AHUs should be combined as one multi-zone recirculating unit for these calcs. I'm drawing a blank as to how to calculate this in the 62 calculator or why it would be necessary.

In Dual Duct unit in the Heating Calc sheet, would I assume the fully occupied Interior Classrooms or conference rooms to be in cooling within the heating calcs for the unit? So this unit's calculation for heating would be a mixture of zones in heating and/or cooling? being these rooms not likely to set Ev.

thanks in advance!