Hello everyone,

I have a project for a warehouse, in which there are areas for storage and manufacturing of plastics. For the air conditioning system, two water cooled chillers are used. Chillers serve two functions:
- Cooling of spaces: the chillers are connected with some AHU's to cool the spaces, and keep them at a temperature of 24°C. The connection from the chillers to the AHUs is direct.
- Process water cooling: there are plastic extrusion machines that use chilled water as a cooling fluid. The connection from the chillers to the machines is NOT direct, there is a plate heat exchanger between the chillers and the extrusion machines. Process cooling Btu/h information is available.

Here are my considerations that should be made for the baseline:
- According to the number of floors, conditioned area and heating source, the HVAC system would be 6: Packaged VAV with PFP Boxes. I will use this system only to model the cooling of spaces. Each element (cooling coil, fans, etc) will be modeled according to Appendix G.
- My main question is the following: to model the process water in the baseline, the chilled water system should be maintained (with the two chillers, cooling towers and pumps). But should the efficiencies be the same as proposed or would they be modeled with ASHRAE 90.1 efficiencies? The chillers in the proposed system are very efficient, I think credit should be given to these chillers for process water as well. In the same way, the modeling of cooling towers and pumps will be according to the proposed design or should it be according to Appendix G?

I would like to read your comments/suggestions for modeling process water in the baseline.

Regards,
Antonio