I need your professional opinion about a project that I am currently working on.
The HVAC zones and zone groups tree is like: Group 1>A(5)>A.1(Master), A.2, A.3, A.4 and A.5. They are 5 different spaces (corridor, offices, conference, and storage). These five rooms are conditioned by one RTU. Room A.1 is the master room and where the thermostat is. The other rooms will only be conditioned when the master room is conditioned.
I have two questions.
First, can I treat these 5 zones as 5 different HVAC zones even though they are conditioned by one RTU?
HVAC zone definition from ASHRAE: a space or group of spaces within a building with heating and cooling requirements that are sufficiently similar so that desired conditions (e.g., temperature) can be maintained throughout using a single sensor (e.g., thermostat or temperature sensor)
If they are 5 different HVAC zones, this means that I have 5 different thermal blocks. Per ASHRAE 90.1-2013 Table G3.1 No. 7, each HVAC zone shall be modeled as a separate thermal block.
The proposed project uses over 30 RTUs. When creating the baseline for this project, system 6 should be utilized. My second question pertains to the RTUS. Can the RTUs be simply replaced by fan-powered boxes (which means one fan power box conditions multiple thermal blocks) or should one fan-powered box be assigned to one thermal block?