modelTableData2DLoadDep

Information

This is a model for cooling-only or heat recovery chillers where the capacity and power are interpolated from manufacturer data along three variables.

• Evaporator entering or leaving temperature: the choice between the entering or leaving temperature depends on the value of the parameter use_TEvaOutForTab specified in the parameter record ( Buildings.Fluid.Chillers.ModularReversible.Data.TableData2DLoadDep.Generic).
• Condenser entering or leaving temperature: the choice between the entering or leaving temperature depends on the value of the parameter use_TConOutForTab specified in the parameter record.
• Compressor part load ratio (PLR): the part load ratio is used as a proxy variable for the actual capacity modulation observable. A discrete observable such as the number of operating compressors for systems with multiple on/off compressors is converted into a continuous PLR value and the model only approximates the system performance on a time average.

The model includes ideal controls that solve for the CHW or HW supply or return temperature setpoint within the capacity limit. The Boolean parameter use_TLoaLvgForCtl is used for toggling between supply or return temperature control. The default setting use_TLoaLvgForCtl=true corresponds to supply temperature control.

For a comprehensive description of the algorithm and the calculations for capacity and power, please refer to the documentation of Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.BaseClasses.TableData2DLoadDep. This documentation also details the required format for the performance data file.

Control points

The following input points are available.

• Chiller on/off command signal: on (Boolean, scalar)
• For heat recovery chillers only (have_switchover=true), chiller switchover signal: coo (Boolean, scalar)
  Set coo=true for cooling mode, coo=false for heating mode.
• CHW temperature setpoint: TChwSet (real, scalar)
  This is either the supply or return temperature setpoint depending on the value of use_TLoaLvgForCtl.
• For heat recovery chillers only (have_switchover=true), HW temperature setpoint: THwSet (real, scalar)
  This is either the supply or return temperature setpoint depending on the value of use_TLoaLvgForCtl.

Implementation details

This model introduces structural changes compared to other models within Buildings.Fluid.Chillers.ModularReversible.

First, there is no replaceable heating cycle component. Instead, the Boolean parameter have_switchover is used for toggling between cooling-only and heat recovery chillers. A major implication is that a single performance data file is used to represent heating and cooling modes in the case of heat recovery chillers. This data file only provides the maximum cooling heat flow rate and input power.

Second, the model includes new input variables that match the control points found in chiller onboard controllers (see the previous section for their description).

Parameters

Connectors

Components

Contents

Name	Description
RefrigerantCycleChillerCooling	Refrigerant cycle module for the cooling mode

Revisions

• March 23, 2026, by Antoine Gautier:
  Refactored with two separate connectors for CHW and HW temperature setpoints.
  This is for #4507.
• March 21, 2025, by Antoine Gautier:
  First implementation.