Appendix G Baseline system - VVT

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Greetings everyone,

I was hoping someone could weigh in on this one:

I'm doing a PRM model for LEED EAc1. My proposed system is a packaged VVT
system for an office building. There are 3 individual offices and an open
office area, each of which has a VVT controller to modulate the airflow into
that zone, all air coming from the one packaged rooftop heat pump. Appendix
G indicates packaged single-zone heat pump as the baseline system.

My questions are:

1. If 'thermal blocks' or zones need to be the same in baseline and
proposed cases, do I model the office as one zone or four zones? If one
zone, the nature of the VVT controls will not be accurately modeled. If four
zones, the baseline system will not be 'Single-zone', or it will assign 4
heat pumps (one per zone).

2. I am using eQuest, and I just played around in the wizard with the
office modeled as a single zone. When I toggle from 'Packaged Single-Zone
Heat Pump' to 'Packaged VVT' in 'system type' box, the VVT shows higher
space cooling energy and lower fan energy than PSZHP. I thought it was going
to be the other way. I feel like I'm not understanding this correctly, so if
anyone could explain this result to me briefly, I would appreciate it.

Thanks in advance for any feedback.

Duke Graham, PE, LEEDR AP

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