Modelling Constraint for Coil:Cooling:WaterToAirHeatPump
I want to use Coil:Cooling:WaterToAirHeatPump:EquationFit in a normal air loop i.e. AirLoopHVAC.
I entered the Coil:Cooling:WaterToAirHeatPump:EquationFit object in Branch, and I got the following severe error. EnergyPlus is V24-1-0.
** Severe ** GetAirPathData: AirLoopHVAC = "CRAH".
** ~~~ ** ..Invalid Air Loop Component Type = "COIL:COOLING:WATERTOAIRHEATPUMP:EQUATIONFIT".
** ~~~ ** ..Air Loop Component Name = "DX COOLING COIL".
** ~~~ ** ..reference Branch = "CRAH MAIN BRANCH".
** Fatal ** GetAirPathData: Errors found retrieving input for AirLoopHVAC.
...Summary of Errors that led to program termination:IDF Editor shows the object in a drop-down list in Branch, so I thought we can use it, but the error says it is invalid.
When I check ExampleFiles, Coil:Cooling:WaterToAirHeatPump:XXX object is always used with AirLoopHVAC:UnitaryHeatPump:waterToAir. Do we have to use Coil:Cooling:WaterToAirHeatPump:XXX with AirLoopHVAC:UnitaryHeatPump:waterToAir? I don't want to use AirLoopHVAC:UnitaryHeatPump:waterToAir because it allows Fan:OnOff only. My system is variable air flow. Is there any way to use Coil:Cooling:WaterToAirHeatPump:XXX without AirLoopHVAC:UnitaryHeatPump:waterToAir?
Hi Keigo, I'm a design builder user who often wants to use water to air coils. I can access these coils from two objects: the unitary heat pump: water to air, or (what design builder calls) generic unitary system air loop. https://bigladdersoftware.com/epx/doc... In the later object, you can have variable air flow. I think the E+ object is called AirLoopHVAC:UnitarySystem https://bigladdersoftware.com/epx/doc...
@Greg Estep Thanks. Right, I also self-resolevd.
@Greg Estep Btw, can DesignBuilder add a precooling coil in front of the unitary heat pump: water to air or generic unitary system? We can model the precooling coil with IDF Editor, but I'm not sure if we can also model it with DB.
@Greg Estep I mean for supply air precooling just upstream of the unitary system, not for outdoor air precooling.
No. I can only place a coil in the outdoor air inlet box (upstream of the mixing damper) Is your AHU just recirculating (no ventilation)?