For Leed EA C1.3 calcs to comply with Core Perf Guide:
We will provide load calcs, zone by zone load calcs at design conditions, Fan sizing calcs, critical path supply duct pressure load calcs and part load condition calcs.
10 story building
6th floor occupied by one tenant
Chilled water AHU unit on floor in mech room
Series VAV boxes, cooling interior, elec heating exterior
DOAS - RTU provides 15% OA. OA is cooled by chilled water to 55degf. No heating. Total energy wheel
Heating only by Series boxes not at DOAS
Project not performing energy modeling. will use prescriptive path using Core Performance Guide. (This is for LEED EA C1.3)
Load calcs were performed in Trace, will upload for heating and cooling loads at design conditions and full occupancy.
Will upload zone by zone load calcs at design conditions
The AHU and main duct loop was designed and built by base building contractor. We will perform calcs for the fan sizing and also the duct loop for static pressure to demonstrate design capacity of the system.
Need to provide part load calculations for this system.
Is there a standard AHRI or Ashrae criteria for this?
Standard outdoor conditions are 95DB/78WB, and indoor are 75/62.5
Can 50% occupancy and 85DB/70WB be used arbitrarily to establish part load conditions for the purpose of this calc, run it in trace and see what tonnage is?
Will this work or can this point only be achieved by full energy simulation? We are not modifying base building systems and it does not seem like practical to do energy modeling for the entire building.
The AHU only serves this floor, which is 100% of the capacity of the unit. However, the chiller serves 9 other floors also, which are same size.
How do we determine motor demand at 50% of design flow for the existing unit fan? It was installed in ~2010