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I've checked all the available example files (especially 5ZoneWaterLoopHeatPump.idf and HospitalLowEnergy.idf), and done my own experimentation. I'm wondering what's really the best way to model a Water Source Heat Pump Loop with the following characteristics:

• There is one heating element (a HeatExchanger:FluidToFluid with Control Type set to HeatingSetpointModulated, but could be a Boiler:HotWater)
• There is one cooling element (a HeatExchanger:FluidToFluid set to CoolingSetpointModulated, but could be aChiller:Electric:EIR)
• The loop temperature should be between 18C (heating dominated) and 26C (cooling dominated), nothing to do in between.

A few options emerge:

• Should the heating element and cooling elements be:
  • in parallel, or,
  • on the same branch?

• Should the Plant Loop Demand Calculation Scheme be:

  • DualSetpointWithDeadband: place a SetpointManager:Scheduled:DualSetpoint with a high temp schedule of 26C and a low temp schedule of 18C on the supply outlet of the plant loop, the heating element outlet node, and the cooling element outlet node (note: all SPMs must be DualSetpoint in this case, meaning SetpointManager:Scheduled isn't an option for each equipment outlet) (5ZoneWaterLoopHeatPump)
  • SingleSetpoint: place a SetpointManager:Scheduled on the supply outlet of the plant loop, actuate this setpoint schedule value with EMS by looking at the supply pump outlet temp: if pump outlet temp <= 18 then 18C, else if over 26C then 26C, in else plant supply outlet temp = pump outlet temp (HospitalLowEnergy). Should you place a SPM:Scheduled with a value of 18C after the heating element and one with 26C after the cooling element?

• What PlantEquipmentOperationScheme to use? I'd use a PlantEquipmentOperation:HeatingLoad with the heating element on it, and a PlantEquipmentOperation:CoolingLoad with the cooling element on it. (HospitalLowEnergy also uses a PlantEquipmentOperaiton:ComponentSetpoint

Thoughts? Proof that the loop temp is controlled properly?

I've checked all the available example files (especially 5ZoneWaterLoopHeatPump.idf and HospitalLowEnergy.idf), and done my own experimentation. I'm wondering what's really the best way to model a Water Source Heat Pump Loop with the following characteristics:

• There is one heating element (a HeatExchanger:FluidToFluid with Control Type set to HeatingSetpointModulated, but could be a Boiler:HotWater)
• There is one cooling element (a HeatExchanger:FluidToFluid set to CoolingSetpointModulated, but could be aChiller:Electric:EIR)
• The loop temperature should be between 18C (heating dominated) and 26C (cooling dominated), nothing to do in between.

A few options emerge:

• Should the heating element and cooling elements be:
  • in parallel, or,
  • on the same branch?

• Should the Plant Loop Demand Calculation Scheme be:

  • DualSetpointWithDeadband: place a SetpointManager:Scheduled:DualSetpoint with a high temp schedule of 26C and a low temp schedule of 18C on the supply outlet of the plant loop, the heating element outlet node, and the cooling element outlet node (note: all SPMs must be DualSetpoint in this case, meaning SetpointManager:Scheduled isn't an option for each equipment outlet) (5ZoneWaterLoopHeatPump)
  • SingleSetpoint: place a SetpointManager:Scheduled on the supply outlet of the plant loop, actuate this setpoint schedule value with EMS by looking at the supply pump outlet temp: if pump outlet temp <= 18 then 18C, else if over 26C then 26C, in else plant supply outlet temp = pump outlet temp (HospitalLowEnergy). Should you place a SPM:Scheduled with a value of 18C after the heating element and one with 26C after the cooling element?

• What PlantEquipmentOperationScheme to use? I'd use a PlantEquipmentOperation:HeatingLoad with the heating element on it, and a PlantEquipmentOperation:CoolingLoad with the cooling element on it. (HospitalLowEnergy also uses a PlantEquipmentOperaiton:ComponentSetpointPlantEquipmentOperation:ComponentSetpoint

Thoughts? Proof that the loop temp is controlled properly?

I've checked all the available example files (especially 5ZoneWaterLoopHeatPump.idf and HospitalLowEnergy.idf), and done my own experimentation. I'm wondering what's really the best way to model a Water Source Heat Pump Loop with the following characteristics:

• There is one heating element (a HeatExchanger:FluidToFluid with Control Type set to HeatingSetpointModulated, but could be a Boiler:HotWater)
• There is one cooling element (a HeatExchanger:FluidToFluid set to CoolingSetpointModulated, but could be aChiller:Electric:EIR)
• The loop temperature should be between 18C (heating dominated) and 26C (cooling dominated), nothing to do in between.

A few options emerge:

• Should the heating element and cooling elements be:
  • in parallel, or,
  • on the same branch?

• Should the Plant Loop Demand Calculation Scheme be:

  • DualSetpointWithDeadband: place a SetpointManager:Scheduled:DualSetpoint with a high temp schedule of 26C and a low temp schedule of 18C on the supply outlet of the plant loop, the heating element outlet node, and the cooling element outlet node (note: all SPMs must be DualSetpoint in this case, meaning SetpointManager:Scheduled isn't an option for each equipment outlet) (5ZoneWaterLoopHeatPump)
  • SingleSetpoint: place a SetpointManager:Scheduled on the supply outlet of the plant loop, actuate this setpoint schedule value with EMS by looking at the supply pump outlet temp: if pump outlet temp <= 18 then 18C, else if over 26C then 26C, in else plant supply outlet temp = pump outlet temp (HospitalLowEnergy). Should you place a SPM:Scheduled with a value of 18C after the heating element and one with 26C after the cooling element?

• What PlantEquipmentOperationScheme to use? I'd use a PlantEquipmentOperation:HeatingLoad with the heating element on it, and a PlantEquipmentOperation:CoolingLoad with the cooling element on it. (HospitalLowEnergy also uses a PlantEquipmentOperation:ComponentSetpoint)

Thoughts? Proof that the loop temp is controlled properly?