We recently recied following review comment for one of the retail project based in taiwan. The project is using VRF System for cooling. The VRF comes with multispeed fan.
"1. The narrative within PI Project Information states that the project is using VRF systems and manufacture model number shown in the mechanical schedules appear to indicate that the system fans are multispeed fans; however, the mechanical plan and schedule do not verify that the multispeed fans operate on the lowest setting when the project space is unoccupied. Note that for VRF systems, fan coils, or packaged single-zone systems, this credit requires that the fan coil or system fan that serves the space to cycle on and off with loads or, for multispeed fans, to operate on the lowest setting when the space is unoccupied.
Provide additional documentation, such as sequence of operation and/or mechanical control diagrams, to confirm that the VRF systems multispeed fans operate on the lowest setting when the project space is unoccupied."
We discussed this with MEP consultant and the contractor. They said the VRF, although having ability to run at multiple speed, actually runs at constant speed during occupancy. It automatically shuts off at 11 PM when the shops closes. And automatically start operating at 9 AM the next morning. From my understnading, Lowest setting is the lowest operational speed of the fan, but during unoccupancy, running the fan at lowest speed means additional fan pwer is wasted, because the shop is closed. Or, does lowest setting means "OFF" here, during unoccupancy? What is the best way to anwser this?