Hi All,

I am doing an Appendix G model for LEED. The proposed building uses a VRV
system where each room has individual control over its own VRV unit. All of
the VRV units share 2 heat pumps. My problem is this: Since each room has
individual control, each room is a 'thermal block'. I have combined as many
as I can according to the Appendix G rules. However, I still have many
thermal blocks. For the baseline, I am required to model a PSZ-HP (packaged
roof top unit heat pump) for each thermal block. This is giving a bunch of
tiny rooms their own individual RTUs, which seems ridiculous and it is
driving my baseline energy use higher than reasonable (primarily in heating
energy.not sure why).

I am modeling in TRACE, giving one SYSTEM per thermal block, and one PLANT
per SYSTEM. If I am allowed to connect all of my systems to just one plant,
my energy use becomes more reasonable.but this seems to go against Appendix
G.

Has anyone come across this issue when modeling a baseline for a proposed
VRV system?

Thanks,

Christian Kaltreider, LEED AP