From ae05585081c94209d0a49be8076ba6825bd42831 Mon Sep 17 00:00:00 2001 From: Joe Robertson Date: Tue, 24 Feb 2026 11:39:06 -0700 Subject: [PATCH 1/4] Clean up doc fields for DesignSpecification:ZoneHVAC:Sizing and Sizing:System. --- .../src/overview/group-design-objects.tex | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/doc/input-output-reference/src/overview/group-design-objects.tex b/doc/input-output-reference/src/overview/group-design-objects.tex index 1da53ccedce..58ecfbe5be1 100644 --- a/doc/input-output-reference/src/overview/group-design-objects.tex +++ b/doc/input-output-reference/src/overview/group-design-objects.tex @@ -1504,7 +1504,7 @@ \subsubsection{Inputs}\label{inputs-5-007} \paragraph{Field Cooling Design Capacity Method}\label{field-cooling-design-capacity-method} -Enter the method used to determine the cooling design capacity for scalable sizing. Input allowed is either \emph{None}, \emph{CoolingDesignCapacity}, \emph{CapacityPerFloorArea}, and \emph{FractionOfAutosizedCoolingCapacity}. None is used when a cooling coil is not included in the Zone HVAC equipment or this field may be left blank. If this input field is left blank, then the design cooling capacity is set to zero. \emph{CoolingDesignCapacity} means user specifies the magnitude of cooling capacity or the program calculates the design cooling capacity if autosize is specified. \emph{CapacityPerFloorArea} means the program calculates the design cooling capacity from user specified cooling capacity per floor area and floor area of the zone served by the HVAC unit. \emph{FractionOfAutosizedCoolingCapacity} means the program calculates the design cooling capacity from user specified fraction and the auto-sized design cooling capacity. The default method is \emph{CoolingDesignCapacity}. +Enter the method used to determine the cooling design capacity for scalable sizing. Input allowed is either \emph{None}, \emph{CoolingDesignCapacity}, \emph{CapacityPerFloorArea}, and \emph{FractionOfAutosizedCoolingCapacity}. None is used when a cooling coil is not included in the zone HVAC equipment or this field may be left blank. If this input field is left blank, then the design cooling capacity is set to zero. \emph{CoolingDesignCapacity} means user specifies the magnitude of cooling capacity or the program calculates the design cooling capacity if autosize is specified. \emph{CapacityPerFloorArea} means the program calculates the design cooling capacity from user specified cooling capacity per floor area and floor area of the zone served by the HVAC unit. \emph{FractionOfAutosizedCoolingCapacity} means the program calculates the design cooling capacity from user specified fraction and the auto-sized design cooling capacity. The default method is \emph{CoolingDesignCapacity}. \paragraph{Field: Cooling Design Capacity \{W\}}\label{field-cooling-design-capacity-w} @@ -1520,7 +1520,7 @@ \subsubsection{Inputs}\label{inputs-5-007} \paragraph{Field: Heating Design Capacity Method}\label{field-heating-design-capacity-method} -Enter the method used to determine the heating design capacity for scalable sizing. Input allowed is either \emph{None}, \emph{HeatingDesignCapacity}, \emph{CapacityPerFloorArea}, and \emph{FractionOfAutosizedHeatingCapacity}. None is used when a heating coil is not included in the Zone HVAC equipment or this field may be left blank. If this input field is left blank, then the design heating capacity is set to zero. \emph{HeatingDesignCapacity} means user specifies the magnitude of heating capacity or the program calculates the design heating capacity if autosize is specified. \emph{CapacityPerFloorArea} means the program calculates the design heating capacity from user specified heating capacity per floor area and floor area of the zone served by the HVAC unit. \emph{FractionOfAutosizedHeatingCapacity} means the program calculates the design heating capacity from user specified fraction and the auto-sized design heating capacity. The default method is \emph{HeatingDesignCapacity}. +Enter the method used to determine the heating design capacity for scalable sizing. Input allowed is either \emph{None}, \emph{HeatingDesignCapacity}, \emph{CapacityPerFloorArea}, and \emph{FractionOfAutosizedHeatingCapacity}. None is used when a heating coil is not included in the zone HVAC equipment or this field may be left blank. If this input field is left blank, then the design heating capacity is set to zero. \emph{HeatingDesignCapacity} means user specifies the magnitude of heating capacity or the program calculates the design heating capacity if autosize is specified. \emph{CapacityPerFloorArea} means the program calculates the design heating capacity from user specified heating capacity per floor area and floor area of the zone served by the HVAC unit. \emph{FractionOfAutosizedHeatingCapacity} means the program calculates the design heating capacity from user specified fraction and the auto-sized design heating capacity. The default method is \emph{HeatingDesignCapacity}. \paragraph{Field: Heating Design Capacity \{W\}}\label{field-heating-design-capacity-w} @@ -1532,7 +1532,7 @@ \subsubsection{Inputs}\label{inputs-5-007} \paragraph{Field: Fraction of Autosized Heating Design Capacity}\label{field-fraction-of-autosized-heating-design-capacity} -Enter the heating capacity as a fraction of the autosized heating capacity. This input field is required when the Heating Design Capacity Method is \emph{FractionOfAutosizedHeatingCapacity}. This input field may be left blank if a heating coil is not included in the zone HVAC equipment or the Heating Design Capacity Method is not \emph{FractionOfAutosizedHeatingCapacity}. The program calculates the heating capacity from the design autosized cooling capacity and user specified fraction. Design day sizing run must be specified. +Enter the heating capacity as a fraction of the autosized heating capacity. This input field is required when the Heating Design Capacity Method is \emph{FractionOfAutosizedHeatingCapacity}. This input field may be left blank if a heating coil is not included in the zone HVAC equipment or the Heating Design Capacity Method is not \emph{FractionOfAutosizedHeatingCapacity}. The program calculates the heating capacity from the design autosized heating capacity and user specified fraction. Design day sizing run must be specified. \begin{lstlisting} DesignSpecification:ZoneHVAC:Sizing, @@ -1816,7 +1816,7 @@ \subsubsection{Inputs}\label{inputs-6-006} \paragraph{Field: Cooling Design Capacity \{W\}}\label{field-cooling-design-capacity-w-1} -Enter the magnitude of the cooling capacity in Watts. This input is an alternative to using the program auto-calculated cooling capacity value. This input is a required field when the Cooling Design Capacity Method is \emph{CoolingDesignCapacity}. This field may be left blank if a cooling coil is not included in the air loop or alternative method is specified. This input field is autosizable. +Enter the magnitude of the cooling capacity in Watts. This input is an alternative to using the program auto-calculated cooling capacity value. This input is a required field when the Cooling Design Capacity Method is \emph{CoolingDesignCapacity}. This field may be left blank if a cooling coil is not included in the airloop or alternative method is specified. This input field is autosizable. \paragraph{Field: Cooling Design Capacity Per Floor Area \{W/m2\}}\label{field-cooling-design-capacity-per-floor-area-wm2-1} @@ -1824,7 +1824,7 @@ \subsubsection{Inputs}\label{inputs-6-006} \paragraph{Field: Fraction of Autosized Cooling Design Capacity}\label{field-fraction-of-autosized-cooling-design-capacity-1} -Enter the cooling capacity as a fraction of the autosized cooling capacity. This input field is required when the Cooling Design Capacity Method is \emph{FractionOfAutosizedCoolingCapacity}. This input field may be left blank if a cooling coil is not included in the zone HVAC equipment or the Cooling Design Capacity Method is not \emph{FractionOfAutosizedCoolingCapacity}. The program calculates the cooling capacity from the design autosized cooling capacity and user specified fraction. Design day sizing run must be specified. +Enter the cooling capacity as a fraction of the autosized cooling capacity. This input field is required when the Cooling Design Capacity Method is \emph{FractionOfAutosizedCoolingCapacity}. This input field may be left blank if a cooling coil is not included in the airloop or the Cooling Design Capacity Method is not \emph{FractionOfAutosizedCoolingCapacity}. The program calculates the cooling capacity from the design autosized cooling capacity and user specified fraction. \paragraph{Field: Heating Design Capacity Method}\label{field-heating-design-capacity-method-1} @@ -1840,7 +1840,7 @@ \subsubsection{Inputs}\label{inputs-6-006} \paragraph{Field: Fraction of Autosized Heating Design Capacity}\label{field-fraction-of-autosized-heating-design-capacity-1} -Enter the heating capacity as a fraction of the autosized heating capacity. This input field is required when the Heating Design Capacity Method is FractionOfAutosizedHeatingCapacity. This input field may be left blank if heating coil is not included in the airloop or the Heating Design Capacity Method is not FractionOfAutosizedHeatingCapacity. The program calculates the heating capacity from the design autosized cooling capacity and user specified fraction. +Enter the heating capacity as a fraction of the autosized heating capacity. This input field is required when the Heating Design Capacity Method is \emph{FractionOfAutosizedHeatingCapacity}. This input field may be left blank if a heating coil is not included in the airloop or the Heating Design Capacity Method is not \emph{FractionOfAutosizedHeatingCapacity}. The program calculates the heating capacity from the design autosized heating capacity and user specified fraction. \paragraph{Field: Central Cooling Capacity Control Method}\label{field-central-cooling-capacity-control-method} From 101c09c13c229f22e3db945f690fa731f7c6f1a0 Mon Sep 17 00:00:00 2001 From: Joe Robertson Date: Tue, 24 Feb 2026 13:33:10 -0700 Subject: [PATCH 2/4] Assign the previously unused heatingCapacityMultiplier variable in UnitarySystem.cc. --- src/EnergyPlus/UnitarySystem.cc | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/EnergyPlus/UnitarySystem.cc b/src/EnergyPlus/UnitarySystem.cc index 123b403da79..f93a8d691b2 100644 --- a/src/EnergyPlus/UnitarySystem.cc +++ b/src/EnergyPlus/UnitarySystem.cc @@ -1911,6 +1911,7 @@ namespace UnitarySystems { bool errorsFound = false; HeatingCapacitySizer sizerHeatingCapacity; sizerHeatingCapacity.overrideSizingString(SizingString); + state.dataSize->DataFracOfAutosizedHeatingCapacity = heatingCapacityMultiplier; sizerHeatingCapacity.initializeWithinEP(state, CompType, CompName, PrintFlag, RoutineName); HeatCapAtPeak = sizerHeatingCapacity.size(state, TempSize, errorsFound); if (state.dataSize->CurSysNum > 0) { @@ -1936,6 +1937,7 @@ namespace UnitarySystems { bool errorsFound = false; HeatingCapacitySizer sizerHeatingCapacity; sizerHeatingCapacity.overrideSizingString(SizingString); + state.dataSize->DataFracOfAutosizedHeatingCapacity = heatingCapacityMultiplier; sizerHeatingCapacity.initializeWithinEP(state, CompType, CompName, PrintFlag, RoutineName); HeatCapAtPeak = sizerHeatingCapacity.size(state, TempSize, errorsFound); if (state.dataSize->CurSysNum > 0) { From 6c692b3401ff219503c5e1513edd8887e543d37e Mon Sep 17 00:00:00 2001 From: Joe Robertson Date: Wed, 25 Feb 2026 10:51:18 -0700 Subject: [PATCH 3/4] Slight modifications to AirflowNetwork_MultiZone_House_OvercoolDehumid.idf so we can test Sizing:System autosized heating fraction with AirLoopHVAC:UnitaryHeatCool. --- ...irflowNetwork_MultiZone_House_OvercoolDehumid.idf | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/testfiles/AirflowNetwork_MultiZone_House_OvercoolDehumid.idf b/testfiles/AirflowNetwork_MultiZone_House_OvercoolDehumid.idf index 05dd13584ce..2192e439ef1 100644 --- a/testfiles/AirflowNetwork_MultiZone_House_OvercoolDehumid.idf +++ b/testfiles/AirflowNetwork_MultiZone_House_OvercoolDehumid.idf @@ -2231,10 +2231,10 @@ autosize, !- Cooling Design Capacity {W} , !- Cooling Design Capacity Per Floor Area {W/m2} , !- Fraction of Autosized Cooling Design Capacity - HeatingDesignCapacity, !- Heating Design Capacity Method + FractionOfAutosizedHeatingCapacity, !- Heating Design Capacity Method autosize, !- Heating Design Capacity {W} , !- Heating Design Capacity Per Floor Area {W/m2} - , !- Fraction of Autosized Heating Design Capacity + 1.5, !- Fraction of Autosized Heating Design Capacity VAV; !- Central Cooling Capacity Control Method AirLoopHVAC:UnitaryHeatCool, @@ -2244,8 +2244,8 @@ Air Loop Outlet Node, !- Unitary System Air Outlet Node Name CyclingFanSchedule, !- Supply Air Fan Operating Mode Schedule Name 50, !- Maximum Supply Air Temperature {C} - 1.02, !- Cooling Supply Air Flow Rate {m3/s} - 1.02, !- Heating Supply Air Flow Rate {m3/s} + autosize, !- Cooling Supply Air Flow Rate {m3/s} + autosize, !- Heating Supply Air Flow Rate {m3/s} 0, !- No Load Supply Air Flow Rate {m3/s} LIVING ZONE, !- Controlling Zone or Thermostat Location Fan:OnOff, !- Supply Fan Object Type @@ -2325,7 +2325,7 @@ HVACAvailSched, !- Availability Schedule Name NaturalGas, !- Fuel Type 0.8, !- Burner Efficiency - 25000, !- Nominal Capacity {W} + autosize, !- Nominal Capacity {W} Heating Coil Air Inlet Node, !- Air Inlet Node Name Fan Inlet Node; !- Air Outlet Node Name @@ -2334,7 +2334,7 @@ HVACAvailSched, !- Availability Schedule Name NaturalGas, !- Fuel Type 0.8, !- Burner Efficiency - 25000, !- Nominal Capacity {W} + autosize, !- Nominal Capacity {W} Reheat Coil Air Inlet Node, !- Air Inlet Node Name Air Loop Outlet Node; !- Air Outlet Node Name From 0f486c604275b854e7aa525eadda0dda953c085b Mon Sep 17 00:00:00 2001 From: Joe Robertson Date: Wed, 25 Feb 2026 15:22:27 -0700 Subject: [PATCH 4/4] Revert cooling to heating change for fraction autosized heating; add design day sentence for applicable Sizing:System fields. --- .../src/overview/group-design-objects.tex | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/doc/input-output-reference/src/overview/group-design-objects.tex b/doc/input-output-reference/src/overview/group-design-objects.tex index 58ecfbe5be1..e4904d5f4d3 100644 --- a/doc/input-output-reference/src/overview/group-design-objects.tex +++ b/doc/input-output-reference/src/overview/group-design-objects.tex @@ -1532,7 +1532,7 @@ \subsubsection{Inputs}\label{inputs-5-007} \paragraph{Field: Fraction of Autosized Heating Design Capacity}\label{field-fraction-of-autosized-heating-design-capacity} -Enter the heating capacity as a fraction of the autosized heating capacity. This input field is required when the Heating Design Capacity Method is \emph{FractionOfAutosizedHeatingCapacity}. This input field may be left blank if a heating coil is not included in the zone HVAC equipment or the Heating Design Capacity Method is not \emph{FractionOfAutosizedHeatingCapacity}. The program calculates the heating capacity from the design autosized heating capacity and user specified fraction. Design day sizing run must be specified. +Enter the heating capacity as a fraction of the autosized heating capacity. This input field is required when the Heating Design Capacity Method is \emph{FractionOfAutosizedHeatingCapacity}. This input field may be left blank if a heating coil is not included in the zone HVAC equipment or the Heating Design Capacity Method is not \emph{FractionOfAutosizedHeatingCapacity}. The program calculates the heating capacity from the design autosized cooling capacity and user specified fraction. Design day sizing run must be specified. \begin{lstlisting} DesignSpecification:ZoneHVAC:Sizing, @@ -1816,7 +1816,7 @@ \subsubsection{Inputs}\label{inputs-6-006} \paragraph{Field: Cooling Design Capacity \{W\}}\label{field-cooling-design-capacity-w-1} -Enter the magnitude of the cooling capacity in Watts. This input is an alternative to using the program auto-calculated cooling capacity value. This input is a required field when the Cooling Design Capacity Method is \emph{CoolingDesignCapacity}. This field may be left blank if a cooling coil is not included in the airloop or alternative method is specified. This input field is autosizable. +Enter the magnitude of the cooling capacity in Watts. This input is an alternative to using the program auto-calculated cooling capacity value. This input is a required field when the Cooling Design Capacity Method is \emph{CoolingDesignCapacity}. This field may be left blank if a cooling coil is not included in the airloop or alternative method is specified. This input field is autosizable. Design day sizing run must be specified. \paragraph{Field: Cooling Design Capacity Per Floor Area \{W/m2\}}\label{field-cooling-design-capacity-per-floor-area-wm2-1} @@ -1824,7 +1824,7 @@ \subsubsection{Inputs}\label{inputs-6-006} \paragraph{Field: Fraction of Autosized Cooling Design Capacity}\label{field-fraction-of-autosized-cooling-design-capacity-1} -Enter the cooling capacity as a fraction of the autosized cooling capacity. This input field is required when the Cooling Design Capacity Method is \emph{FractionOfAutosizedCoolingCapacity}. This input field may be left blank if a cooling coil is not included in the airloop or the Cooling Design Capacity Method is not \emph{FractionOfAutosizedCoolingCapacity}. The program calculates the cooling capacity from the design autosized cooling capacity and user specified fraction. +Enter the cooling capacity as a fraction of the autosized cooling capacity. This input field is required when the Cooling Design Capacity Method is \emph{FractionOfAutosizedCoolingCapacity}. This input field may be left blank if a cooling coil is not included in the airloop or the Cooling Design Capacity Method is not \emph{FractionOfAutosizedCoolingCapacity}. The program calculates the cooling capacity from the design autosized cooling capacity and user specified fraction. Design day sizing run must be specified. \paragraph{Field: Heating Design Capacity Method}\label{field-heating-design-capacity-method-1} @@ -1832,7 +1832,7 @@ \subsubsection{Inputs}\label{inputs-6-006} \paragraph{Field: Heating Design Capacity \{W\}}\label{field-heating-design-capacity-w-1} -Enter the magnitude of the heating capacity in Watts. This input is an alternative to using the program auto-calculated heating capacity value. This input is a required field when the Heating Design Capacity Method is \emph{HeatingDesignCapacity}. This field may be left blank if a heating coil is not included in the airloop or alternative method is specified. This input field is autosizable. +Enter the magnitude of the heating capacity in Watts. This input is an alternative to using the program auto-calculated heating capacity value. This input is a required field when the Heating Design Capacity Method is \emph{HeatingDesignCapacity}. This field may be left blank if a heating coil is not included in the airloop or alternative method is specified. This input field is autosizable. Design day sizing run must be specified. \paragraph{Field: Heating Design Capacity Per Floor Area \{W/m2\}}\label{field-heating-design-capacity-per-floor-area-wm2-1} @@ -1840,7 +1840,7 @@ \subsubsection{Inputs}\label{inputs-6-006} \paragraph{Field: Fraction of Autosized Heating Design Capacity}\label{field-fraction-of-autosized-heating-design-capacity-1} -Enter the heating capacity as a fraction of the autosized heating capacity. This input field is required when the Heating Design Capacity Method is \emph{FractionOfAutosizedHeatingCapacity}. This input field may be left blank if a heating coil is not included in the airloop or the Heating Design Capacity Method is not \emph{FractionOfAutosizedHeatingCapacity}. The program calculates the heating capacity from the design autosized heating capacity and user specified fraction. +Enter the heating capacity as a fraction of the autosized heating capacity. This input field is required when the Heating Design Capacity Method is \emph{FractionOfAutosizedHeatingCapacity}. This input field may be left blank if a heating coil is not included in the airloop or the Heating Design Capacity Method is not \emph{FractionOfAutosizedHeatingCapacity}. The program calculates the heating capacity from the design autosized cooling capacity and user specified fraction. Design day sizing run must be specified. \paragraph{Field: Central Cooling Capacity Control Method}\label{field-central-cooling-capacity-control-method}