All,

I am modeling a portion of a 100% outside air lab in a type 5A climate zone. The area is below ground/has interior walls so there is no fenestration. The system has two chilled water air handling units and VAV boxes with zone reheat. The two AHU's run 24/7 at a constant CFM because the supply air is driven by a required air change rate per room type.
My problem is:
- I have too many unmet cooling hours when allowing e-Quest to auto-size the cooling coil capacity of the air handling units
Diagnosis:
- The delta T of the cooling coil never gets above 7 degrees F any day of the summer.
- e-Quest severely undersized the cooling coils from a design day. (I have calculated the design day cooling load by hand)
- No warnings in the Sim report

I have tried troubleshooting the system for a couple of days but am unable to find the reason e-Quest is under sizing the cooling coil capacity. I have attached the .inp file. Any suggestion are greatly appreciated.

Thank you,
Brad Huff, E.I.T.