Equation Fit Water-to-air Heat Pump Object in OpenStudio

asked 2026-02-18 09:53:50 -0500

TTQI_ML
25 ●2

Hello, I would like to know if there is a way to implement the Coil:WaterToAirHeatPump:EquationFit Energy Plus object within an Airloop in OpenStudio.

I've succeded in extracting the object from the AirLoopHVAC:UnitaryHeatPump:WaterToAir object source code and inserting it into an AirLoop, but I get severe errors stating that the componenet type is invalid ''..Invalid Air Loop Component Type = "COIL:HEATING:WATERTOAIRHEATPUMP:EQUATIONFIT"

The water-to-air unitary heat pump accessible through OpenStudio contains cooling, heating and electric coil; however, the packaged unit I am trying to model only contains a heating coil.

Is there a way to fix the severe error or is there any simpler ways of inserting an equation fit, water-to-air heat pump model in an OpenStudio AirLoop?

Thanks.

answered 2026-02-18 13:08:12 -0500

rraustad

14134 ●88 ●13 http://www.ucf.edu/

This object is not meant to be a component on a branch (e.g., as with a water coil in the AirloopHVAC branch below). This object needs a parent object on the branch to control the operation of the coil and the coil is inside that parent object.

Branch,
  SYS0Branch1,    !- Name
  ,                        !- Pressure Drop Curve Name
  AirLoopHVAC:OutdoorAirSystem,  !- Component 1 Object Type
  SYS0OA System,  !- Component 1 Name
  SYS0Supply Inlet Node,  !- Component 1 Inlet Node Name
  SYS0AirLoopMixed Air Node Name,  !- Component 1 Outlet Node Name
  Coil:Heating:Water,      !- Component 2 Object Type
  SYS0SHC-1,      !- Component 2 Name
  SYS0AirLoopMixed Air Node Name,  !- Component 2 Inlet Node Name
  SYS0SHC-1Outlet Node,  !- Component 2 Outlet Node Name
  CoilSystem:Cooling:DX,   !- Component 3 Object Type
  SYS0SCC-1System,!- Component 3 Name
  SYS0SHC-1Outlet Node,  !- Component 3 Inlet Node Name
  SYS0SCC-1Outlet Node,  !- Component 3 Outlet Node Name
  Fan:SystemModel,         !- Component 4 Object Type
  SYS0SF-1,       !- Component 4 Name
  SYS0SCC-1Outlet Node,  !- Component 4 Inlet Node Name
  SYS0Supply Outlet Node;  !- Component 4 Outlet Node Name