@Dustinl, there is no easy way to do this in CBECC-Com or for compliance. You could make a few assumptions and model it as a more efficient heat pump using a zone system simulating something more similar to a VRF heat pump (VRF without heat sharing), but you won't get the part load performance you would from a true VRF system and CBECC-Com forces you to use a single speed compressor and fan, which doesn't help. Seeing as it is just compliance, you may want to try this and see if it passes. This will largely depend on what your baseline is; if it's chilled water VAV then odds are it won't pass, but if the building is small enough to have a PVAV baseline then it may work.
If you want to model VRF then my suggestion is to take the .osm model produced by CBECC-Com and open it in OpenStudio to create the VRF system as needed. This will mean that you will have to pursue the exceptional compliance pathway, but there isn't any other mechanism to show true performance of most advanced systems. I spoke with an LG rep recently and it looks like a few VRF manufacturers have teamed together to fund a VRF component for CBECC-Com that should be available in v4, which is still a little ways off as the next version coming out is v3c.
