I'm
autosizing HVAC systems according to appendix G of ASHRAE 90.1 (baseline model).
They are Systems 3 (PSZ-AC Packaged rooftop air conditioner).
In a zone where in the real building there is no cooling I have imposed 40°C as cooling setpoint. I can see in the .eso output that during the design day the zone temperature is always less than 40°C and the â??Cooling Coil Total Cooling Rateâ?? (Coil:Cooling:DX:SingleSpeed) is always equal to 0 W. Moreover, in the .html report â??HVAC Sizing Summaryâ?? in the table â??Zone Coolingâ?? the â??Calculated Design Loadâ?? and the â??User Design Loadâ?? are equal to 0. Nevertheless, in the table â??DX cooling coilâ?? of the html report â??Equipment Summaryâ?? the â??Standard Rated Net Cooling Capacity [W]â?? is not 0 (it is quite high? 35603 W). Why? If the design load is 0 andd the coil is autosized, then its capacity should be equal to 0, shouldn't it?
The coil is controlled by SetpointManager:SingleZone:Cooling
The system doesn't provide outdoor air.
In Sizing:System the "Cooling Design Air Flow Method" is DesignDay.
With Regards
Francesco