There are more and more companies making fan coil units with VFD
motors, automatic
variable supply air control rather than traditional 3-speed control,
which gives them variable air volume capability similar to the typical
VAV system (VAV
box/terminal unit). So can variable speed FCUs be treated as VAV systems
in the energy model?

Under 90.1, our system should be compared with System 8 VAV with PFP
box, but I think it would be unfair to us if we just model it as a
constant volume system

Best regards,

James Chueh, LEED(r) AP