zWSHP object input rated (reference) conditions?
Hello all, this question is regarding the rated inputs for object Coil:Cooling:WaterToAirHeatPump:EquationFit
I have a project (hotel) where I want to hard size the heat pumps to match what is shown on the mechanical drawings schedule. OK, this is annoying, but I have model data grid view, and I start bulk editing the inputs. A typical guest room is using the water source HP BOSCH CL 07 unit and has a rated cooling capacity of about 7000 Btu/h and rated airflow of 300 CFM. Great. I run the simulation for the summer design week and get more unmet hours than expected. I look at the cooling coil total cooling rate and find that unit is peaking out at about 3000 Btu/h. This is less than half the output. I try to convince myself this is due to warmer water temperature (75F) and cooler entering air temperature, but I can’t justify a 50% capacity reduction.
The engineering reference says, For cooling mode, the reference conditions; reference load side air volumetric flow rate (˙Vair,ref), reference source side water volumetric flow rate(˙Vw,ref), reference sensible capacity (Qsens,ref) and reference power input (Powerc,ref) are the conditions when the heat pump is operating at the highest cooling capacity or reference cooling capacity (Qtotal,ref) indicated in the manufacturer’s catalog
Question: Are the reference conditions different from AHRI (13256-1)?
