I am simulating DOAS system with an air-cooled DX unit using OpenStudio, and there is an error when sizing the "Coil:Cooling:DX:SingleSpeed".
Based on the "input output reference" of E+, the rated volumetric air flow to total cooling capacity of "Coil:Cooling:DX:SingleSpeed" should be 300 to 450 cfm/ton; for DOAS application, it should be 125 to 250 cfm/ton. My DOAS system is 168 cfm/ton, which locates in the range of DOAS application. However, E+ seems to use the range of 300 to 450 cfm/ton, and it comes out the error:
* Severe * Sizing: Coil:Cooling:DX:SingleSpeed "1 SPD DX CLG COIL": Rated air volume flow rate per watt of rated total cooling capacity is out of range. * ~~~ * ...Air Volume Flow Rate used in calculation = 1.179869 m3/s * ~~~ * ...Air Volume Flow Rate per Watt of Rated Cooling Capacity is also out of bounds at = 2.2566585E-005 m3/s/W * ~~~ * During Warmup, Environment=NEWARK INTERNATIONAL ARPT ANN CLG .4% CONDNS DB=>MWB, at Simulation time=07/21 00:00 - 00:10
How should I let the program know that it is DOAS application?
Here is my setup:
The "Type of Load to Size On" was set as "VentilationRequirement", and both "100% Outdoor Air in Cooling" and "100% Outdoor Air in Heating" as "Yes". As for the "Coil:Cooling:DX:SingleSpeed", cooling capacity is 178400 BTU/h and air flow rate is 2500 cfm
