I've seen the "poor man's VAV" installed on several small commercial jobs in the last few years - that is: packaged constant volume rooftop with zone dampers modulating airflow to spaces and a supply-to-return bypass damper for excess supply air.

Any suggestions which system type to use in eQUEST / DOE-2 for this system?

I've looked at CBVAV, but that requires CHW cooling.

I'm looking at PVVT right now. It requires a variable flow supply fan, though, and doesn't pick up the changed evaporator entering conditions due to the bypassed cool supply air.

Any thoughts?

Aaron Dahlstrom , PE, LEED(r) AP