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CondenserLoop Coincident sizing is larger than NonCoincident sizing

My model is the same as this post, but let me post a different question.

I have a problem with Coincident plant sizing for CondenserLoop. I tried both Coincident sizing and NonCoincident sizing, but the weird thing is that the autosized condenser loop (Cooling towers and condenser water pumps) by Coincident sizing is much larger than that by NonCoincident sizing. It does not happen in PlantLoop (chillers and chilled water pumps). I think my Coincident sizing settings are appropriate.

Below are the sizing results of cooling towers. Autosized condenser water flow rate by Coincndent sizing is 0.164097m3/s, which is more than 2 times larger than the autosized condenser water flow rate of 0.072678m3/s by NonCoincident sizing. Does anyone know why?

image description

My settings related to Coincident sizing are as follows.

    SimulationControl,
        Yes,                     !- Do Zone Sizing Calculation
        Yes,                     !- Do System Sizing Calculation
        Yes,                     !- Do Plant Sizing Calculation
        Yes,                     !- Run Simulation for Sizing Periods
        No,                      !- Run Simulation for Weather File Run Periods
        Yes,                     !- Do HVAC Sizing Simulation for Sizing Periods
        1;                       !- Maximum Number of HVAC Sizing Simulation Passes

    Sizing:Parameters,
        1.25,                    !- Heating Sizing Factor
        1.15;                    !- Cooling Sizing Factor

    Sizing:System,
        VAV_3,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

    Sizing:System,
        VAV_2,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

    Sizing:System,
        VAV_1,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

Sizing:Plant,
    CHWloop Chilled Water Loop,  !- Plant or Condenser Loop Name
    Cooling,                 !- Loop Type
    6.7,                     !- Design Loop Exit Temperature {C}
    6.3,                     !- Loop Design Temperature Difference {deltaC}
    Coincident,              !- Sizing Option
    ,                        !- Zone Timesteps in Averaging Window
    None;                    !- Coincident Sizing Factor Mode

Sizing:Plant,
    CHWloop Condenser Water Loop,  !- Plant or Condenser Loop Name
    Condenser,               !- Loop Type
    29,                      !- Design Loop Exit Temperature {C}
    5.6,                     !- Loop Design Temperature Difference {deltaC}
    Coincident,              !- Sizing Option
    ,                        !- Zone Timesteps in Averaging Window
    None;                    !- Coincident Sizing Factor Mode

CoolingTower:TwoSpeed,
    coolingtower1,           !- Name
    coolingtower1 CndW Inlet,!- Water Inlet Node Name
    coolingtower1 CndW Outlet,  !- Water Outlet Node Name
    autosize,                !- Design Water Flow Rate {m3/s}
    autosize,                !- High Fan Speed Air Flow Rate {m3/s}
    autosize,                !- High Fan Speed Fan Power {W}
    autosize,                !- High Fan Speed U-Factor Times Area Value {W/K}
    autocalculate,           !- Low Fan Speed Air Flow Rate {m3/s}
    ,                        !- Low Fan Speed Air Flow Rate Sizing Factor
    autocalculate,           !- Low Fan Speed Fan Power {W}
    ,                        !- Low Fan Speed Fan Power Sizing Factor
    autocalculate,           !- Low Fan Speed U-Factor Times Area Value {W/K}
    ,                        !- Low Fan Speed U-Factor Times Area Sizing Factor
    autocalculate,           !- Free Convection Regime Air Flow Rate {m3/s}
    ,                        !- Free Convection Regime Air Flow Rate Sizing Factor
    autocalculate,           !- Free Convection Regime U-Factor Times Area Value {W/K}
    ,                        !- Free Convection U-Factor Times Area Value Sizing Factor
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    ,                        !- Heat Rejection Capacity and Nominal Capacity Sizing Ratio
    ,                        !- High Speed Nominal Capacity {W}
    autocalculate,           !- Low Speed Nominal Capacity {W}
    ,                        !- Low Speed Nominal Capacity Sizing Factor
    autocalculate,           !- Free Convection Nominal Capacity {W}
    ,                        !- Free Convection Nominal Capacity Sizing Factor
    ,                        !- Design Inlet Air Dry-Bulb Temperature {C}
    ,                        !- Design Inlet Air Wet-Bulb Temperature {C}
    ,                        !- Design Approach Temperature {deltaC}
    ,                        !- Design Range Temperature {deltaC}
    ,                        !- Basin Heater Capacity {W/K}
    ,                        !- Basin Heater Setpoint Temperature {C}
    ,                        !- Basin Heater Operating Schedule Name
    SaturatedExit,           !- Evaporation Loss Mode
    ,                        !- Evaporation Loss Factor {percent/K}
    0.008,                   !- Drift Loss Percent {percent}
    ConcentrationRatio,      !- Blowdown Calculation Mode
    3,                       !- Blowdown Concentration Ratio
    ,                        !- Blowdown Makeup Water Usage Schedule Name
    ,                        !- Supply Water Storage Tank Name
    coolingtower1 Cooling Tower Outdoor Air Inlet Node,  !- Outdoor Air Inlet Node Name
    ,                        !- Number of Cells
    ,                        !- Cell Control
    ,                        !- Cell Minimum  Water Flow Rate Fraction
    ,                        !- Cell Maximum Water Flow Rate Fraction
    0.5;                     !- Sizing Factor

CoolingTower:TwoSpeed,
    coolingtower2,           !- Name
    coolingtower2 CndW Inlet,!- Water Inlet Node Name
    coolingtower2 CndW Outlet,  !- Water Outlet Node Name
    autosize,                !- Design Water Flow Rate {m3/s}
    autosize,                !- High Fan Speed Air Flow Rate {m3/s}
    autosize,                !- High Fan Speed Fan Power {W}
    autosize,                !- High Fan Speed U-Factor Times Area Value {W/K}
    autocalculate,           !- Low Fan Speed Air Flow Rate {m3/s}
    ,                        !- Low Fan Speed Air Flow Rate Sizing Factor
    autocalculate,           !- Low Fan Speed Fan Power {W}
    ,                        !- Low Fan Speed Fan Power Sizing Factor
    autocalculate,           !- Low Fan Speed U-Factor Times Area Value {W/K}
    ,                        !- Low Fan Speed U-Factor Times Area Sizing Factor
    autocalculate,           !- Free Convection Regime Air Flow Rate {m3/s}
    ,                        !- Free Convection Regime Air Flow Rate Sizing Factor
    autocalculate,           !- Free Convection Regime U-Factor Times Area Value {W/K}
    ,                        !- Free Convection U-Factor Times Area Value Sizing Factor
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    ,                        !- Heat Rejection Capacity and Nominal Capacity Sizing Ratio
    ,                        !- High Speed Nominal Capacity {W}
    autocalculate,           !- Low Speed Nominal Capacity {W}
    ,                        !- Low Speed Nominal Capacity Sizing Factor
    autocalculate,           !- Free Convection Nominal Capacity {W}
    ,                        !- Free Convection Nominal Capacity Sizing Factor
    ,                        !- Design Inlet Air Dry-Bulb Temperature {C}
    ,                        !- Design Inlet Air Wet-Bulb Temperature {C}
    ,                        !- Design Approach Temperature {deltaC}
    ,                        !- Design Range Temperature {deltaC}
    ,                        !- Basin Heater Capacity {W/K}
    ,                        !- Basin Heater Setpoint Temperature {C}
    ,                        !- Basin Heater Operating Schedule Name
    SaturatedExit,           !- Evaporation Loss Mode
    ,                        !- Evaporation Loss Factor {percent/K}
    0.008,                   !- Drift Loss Percent {percent}
    ConcentrationRatio,      !- Blowdown Calculation Mode
    3,                       !- Blowdown Concentration Ratio
    ,                        !- Blowdown Makeup Water Usage Schedule Name
    ,                        !- Supply Water Storage Tank Name
    coolingtower2 Cooling Tower Outdoor Air Inlet Node,  !- Outdoor Air Inlet Node Name
    ,                        !- Number of Cells
    ,                        !- Cell Control
    ,                        !- Cell Minimum  Water Flow Rate Fraction
    ,                        !- Cell Maximum Water Flow Rate Fraction
    0.5;                     !- Sizing Factor

CondenserLoop Coincident sizing is larger than NonCoincident sizing

My model is the same as this post, but let me post a different question.

I have a problem with Coincident plant sizing for CondenserLoop. I tried both Coincident sizing and NonCoincident sizing, but the weird thing is that the autosized condenser loop (Cooling towers and condenser water pumps) by Coincident sizing is much larger than that by NonCoincident sizing. It does not happen in PlantLoop (chillers and chilled water pumps). I think my Coincident sizing settings are appropriate.

Below are the sizing results of cooling towers. Autosized condenser water flow rate by Coincndent sizing is 0.164097m3/s, which is more than 2 times larger than the autosized condenser water flow rate of 0.072678m3/s by NonCoincident sizing. Does anyone know why?

image description

I think the "Initial" values in the html file are the correct ones which are autosized by Coincident sizing. The "Design" values are incorrect. However, this is not just a reporting issue. I also ran annual simulations. The pump end use with Coincident sizing became much larger than that with NonCoincident sizing NonCoincident sizing. EnergyPlus uses the "Design" values.

image description

Is this a bug? Or am I missing something? My settings related to Coincident sizing are as follows.follows. Any suggestions would be appreciated.

    SimulationControl,
        Yes,                     !- Do Zone Sizing Calculation
        Yes,                     !- Do System Sizing Calculation
        Yes,                     !- Do Plant Sizing Calculation
        Yes,                     !- Run Simulation for Sizing Periods
        No,                      !- Run Simulation for Weather File Run Periods
        Yes,                     !- Do HVAC Sizing Simulation for Sizing Periods
        1;                       !- Maximum Number of HVAC Sizing Simulation Passes

    Sizing:Parameters,
        1.25,                    !- Heating Sizing Factor
        1.15;                    !- Cooling Sizing Factor

    Sizing:System,
        VAV_3,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

    Sizing:System,
        VAV_2,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

    Sizing:System,
        VAV_1,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

Sizing:Plant,
    CHWloop Chilled Water Loop,  !- Plant or Condenser Loop Name
    Cooling,                 !- Loop Type
    6.7,                     !- Design Loop Exit Temperature {C}
    6.3,                     !- Loop Design Temperature Difference {deltaC}
    Coincident,              !- Sizing Option
    ,                        !- Zone Timesteps in Averaging Window
    None;                    !- Coincident Sizing Factor Mode

Sizing:Plant,
    CHWloop Condenser Water Loop,  !- Plant or Condenser Loop Name
    Condenser,               !- Loop Type
    29,                      !- Design Loop Exit Temperature {C}
    5.6,                     !- Loop Design Temperature Difference {deltaC}
    Coincident,              !- Sizing Option
    ,                        !- Zone Timesteps in Averaging Window
    None;                    !- Coincident Sizing Factor Mode

CoolingTower:TwoSpeed,
    coolingtower1,           !- Name
    coolingtower1 CndW Inlet,!- Water Inlet Node Name
    coolingtower1 CndW Outlet,  !- Water Outlet Node Name
    autosize,                !- Design Water Flow Rate {m3/s}
    autosize,                !- High Fan Speed Air Flow Rate {m3/s}
    autosize,                !- High Fan Speed Fan Power {W}
    autosize,                !- High Fan Speed U-Factor Times Area Value {W/K}
    autocalculate,           !- Low Fan Speed Air Flow Rate {m3/s}
    ,                        !- Low Fan Speed Air Flow Rate Sizing Factor
    autocalculate,           !- Low Fan Speed Fan Power {W}
    ,                        !- Low Fan Speed Fan Power Sizing Factor
    autocalculate,           !- Low Fan Speed U-Factor Times Area Value {W/K}
    ,                        !- Low Fan Speed U-Factor Times Area Sizing Factor
    autocalculate,           !- Free Convection Regime Air Flow Rate {m3/s}
    ,                        !- Free Convection Regime Air Flow Rate Sizing Factor
    autocalculate,           !- Free Convection Regime U-Factor Times Area Value {W/K}
    ,                        !- Free Convection U-Factor Times Area Value Sizing Factor
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    ,                        !- Heat Rejection Capacity and Nominal Capacity Sizing Ratio
    ,                        !- High Speed Nominal Capacity {W}
    autocalculate,           !- Low Speed Nominal Capacity {W}
    ,                        !- Low Speed Nominal Capacity Sizing Factor
    autocalculate,           !- Free Convection Nominal Capacity {W}
    ,                        !- Free Convection Nominal Capacity Sizing Factor
    ,                        !- Design Inlet Air Dry-Bulb Temperature {C}
    ,                        !- Design Inlet Air Wet-Bulb Temperature {C}
    ,                        !- Design Approach Temperature {deltaC}
    ,                        !- Design Range Temperature {deltaC}
    ,                        !- Basin Heater Capacity {W/K}
    ,                        !- Basin Heater Setpoint Temperature {C}
    ,                        !- Basin Heater Operating Schedule Name
    SaturatedExit,           !- Evaporation Loss Mode
    ,                        !- Evaporation Loss Factor {percent/K}
    0.008,                   !- Drift Loss Percent {percent}
    ConcentrationRatio,      !- Blowdown Calculation Mode
    3,                       !- Blowdown Concentration Ratio
    ,                        !- Blowdown Makeup Water Usage Schedule Name
    ,                        !- Supply Water Storage Tank Name
    coolingtower1 Cooling Tower Outdoor Air Inlet Node,  !- Outdoor Air Inlet Node Name
    ,                        !- Number of Cells
    ,                        !- Cell Control
    ,                        !- Cell Minimum  Water Flow Rate Fraction
    ,                        !- Cell Maximum Water Flow Rate Fraction
    0.5;                     !- Sizing Factor

CoolingTower:TwoSpeed,
    coolingtower2,           !- Name
    coolingtower2 CndW Inlet,!- Water Inlet Node Name
    coolingtower2 CndW Outlet,  !- Water Outlet Node Name
    autosize,                !- Design Water Flow Rate {m3/s}
    autosize,                !- High Fan Speed Air Flow Rate {m3/s}
    autosize,                !- High Fan Speed Fan Power {W}
    autosize,                !- High Fan Speed U-Factor Times Area Value {W/K}
    autocalculate,           !- Low Fan Speed Air Flow Rate {m3/s}
    ,                        !- Low Fan Speed Air Flow Rate Sizing Factor
    autocalculate,           !- Low Fan Speed Fan Power {W}
    ,                        !- Low Fan Speed Fan Power Sizing Factor
    autocalculate,           !- Low Fan Speed U-Factor Times Area Value {W/K}
    ,                        !- Low Fan Speed U-Factor Times Area Sizing Factor
    autocalculate,           !- Free Convection Regime Air Flow Rate {m3/s}
    ,                        !- Free Convection Regime Air Flow Rate Sizing Factor
    autocalculate,           !- Free Convection Regime U-Factor Times Area Value {W/K}
    ,                        !- Free Convection U-Factor Times Area Value Sizing Factor
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    ,                        !- Heat Rejection Capacity and Nominal Capacity Sizing Ratio
    ,                        !- High Speed Nominal Capacity {W}
    autocalculate,           !- Low Speed Nominal Capacity {W}
    ,                        !- Low Speed Nominal Capacity Sizing Factor
    autocalculate,           !- Free Convection Nominal Capacity {W}
    ,                        !- Free Convection Nominal Capacity Sizing Factor
    ,                        !- Design Inlet Air Dry-Bulb Temperature {C}
    ,                        !- Design Inlet Air Wet-Bulb Temperature {C}
    ,                        !- Design Approach Temperature {deltaC}
    ,                        !- Design Range Temperature {deltaC}
    ,                        !- Basin Heater Capacity {W/K}
    ,                        !- Basin Heater Setpoint Temperature {C}
    ,                        !- Basin Heater Operating Schedule Name
    SaturatedExit,           !- Evaporation Loss Mode
    ,                        !- Evaporation Loss Factor {percent/K}
    0.008,                   !- Drift Loss Percent {percent}
    ConcentrationRatio,      !- Blowdown Calculation Mode
    3,                       !- Blowdown Concentration Ratio
    ,                        !- Blowdown Makeup Water Usage Schedule Name
    ,                        !- Supply Water Storage Tank Name
    coolingtower2 Cooling Tower Outdoor Air Inlet Node,  !- Outdoor Air Inlet Node Name
    ,                        !- Number of Cells
    ,                        !- Cell Control
    ,                        !- Cell Minimum  Water Flow Rate Fraction
    ,                        !- Cell Maximum Water Flow Rate Fraction
    0.5;                     !- Sizing Factor

CondenserLoop Coincident sizing is larger than NonCoincident sizing

My model is the same as this post, but let me post a different question.

I have a problem with Coincident plant sizing for CondenserLoop. I tried both Coincident sizing and NonCoincident sizing, but the weird thing is that the autosized condenser loop (Cooling towers and condenser water pumps) by Coincident sizing is much larger than that by NonCoincident sizing. It does not happen in PlantLoop (chillers and chilled water pumps). I think my Coincident sizing settings are appropriate.

Below are the sizing results of cooling towers. Autosized condenser water flow rate by Coincndent sizing is 0.164097m3/s, which is more than 2 times larger than the autosized condenser water flow rate of 0.072678m3/s by NonCoincident sizing. Does anyone know why?

image description

I think the "Initial" values in the html file are the correct ones which are autosized by Coincident sizing. The "Design" values are incorrect. However, this is not just a reporting issue. I also ran annual simulations. The pump end use with Coincident sizing became much larger than that with NonCoincident sizing NonCoincident sizing. EnergyPlus uses the "Design" values.

image description

Is this a bug? Or am I missing something? My settings related to Coincident sizing are as follows. Any suggestions would be appreciated.

    SimulationControl,
        Yes,                     !- Do Zone Sizing Calculation
        Yes,                     !- Do System Sizing Calculation
        Yes,                     !- Do Plant Sizing Calculation
        Yes,                     !- Run Simulation for Sizing Periods
        No,                      !- Run Simulation for Weather File Run Periods
        Yes,                     !- Do HVAC Sizing Simulation for Sizing Periods
        1;                       !- Maximum Number of HVAC Sizing Simulation Passes

    Sizing:Parameters,
        1.25,                    !- Heating Sizing Factor
        1.15;                    !- Cooling Sizing Factor

    Sizing:System,
        VAV_3,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

    Sizing:System,
        VAV_2,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

    Sizing:System,
        VAV_1,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

Sizing:Plant,
    CHWloop Chilled Water Loop,  !- Plant or Condenser Loop Name
    Cooling,                 !- Loop Type
    6.7,                     !- Design Loop Exit Temperature {C}
    6.3,                     !- Loop Design Temperature Difference {deltaC}
    Coincident,              !- Sizing Option
    ,                        !- Zone Timesteps in Averaging Window
    None;                    !- Coincident Sizing Factor Mode

Sizing:Plant,
    CHWloop Condenser Water Loop,  !- Plant or Condenser Loop Name
    Condenser,               !- Loop Type
    29,                      !- Design Loop Exit Temperature {C}
    5.6,                     !- Loop Design Temperature Difference {deltaC}
    Coincident,              !- Sizing Option
    ,                        !- Zone Timesteps in Averaging Window
    None;                    !- Coincident Sizing Factor Mode

CoolingTower:TwoSpeed,
    coolingtower1,           !- Name
    coolingtower1 CndW Inlet,!- Water Inlet Node Name
    coolingtower1 CndW Outlet,  !- Water Outlet Node Name
    autosize,                !- Design Water Flow Rate {m3/s}
    autosize,                !- High Fan Speed Air Flow Rate {m3/s}
    autosize,                !- High Fan Speed Fan Power {W}
    autosize,                !- High Fan Speed U-Factor Times Area Value {W/K}
    autocalculate,           !- Low Fan Speed Air Flow Rate {m3/s}
    ,                        !- Low Fan Speed Air Flow Rate Sizing Factor
    autocalculate,           !- Low Fan Speed Fan Power {W}
    ,                        !- Low Fan Speed Fan Power Sizing Factor
    autocalculate,           !- Low Fan Speed U-Factor Times Area Value {W/K}
    ,                        !- Low Fan Speed U-Factor Times Area Sizing Factor
    autocalculate,           !- Free Convection Regime Air Flow Rate {m3/s}
    ,                        !- Free Convection Regime Air Flow Rate Sizing Factor
    autocalculate,           !- Free Convection Regime U-Factor Times Area Value {W/K}
    ,                        !- Free Convection U-Factor Times Area Value Sizing Factor
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    ,                        !- Heat Rejection Capacity and Nominal Capacity Sizing Ratio
    ,                        !- High Speed Nominal Capacity {W}
    autocalculate,           !- Low Speed Nominal Capacity {W}
    ,                        !- Low Speed Nominal Capacity Sizing Factor
    autocalculate,           !- Free Convection Nominal Capacity {W}
    ,                        !- Free Convection Nominal Capacity Sizing Factor
    ,                        !- Design Inlet Air Dry-Bulb Temperature {C}
    ,                        !- Design Inlet Air Wet-Bulb Temperature {C}
    ,                        !- Design Approach Temperature {deltaC}
    ,                        !- Design Range Temperature {deltaC}
    ,                        !- Basin Heater Capacity {W/K}
    ,                        !- Basin Heater Setpoint Temperature {C}
    ,                        !- Basin Heater Operating Schedule Name
    SaturatedExit,           !- Evaporation Loss Mode
    ,                        !- Evaporation Loss Factor {percent/K}
    0.008,                   !- Drift Loss Percent {percent}
    ConcentrationRatio,      !- Blowdown Calculation Mode
    3,                       !- Blowdown Concentration Ratio
    ,                        !- Blowdown Makeup Water Usage Schedule Name
    ,                        !- Supply Water Storage Tank Name
    coolingtower1 Cooling Tower Outdoor Air Inlet Node,  !- Outdoor Air Inlet Node Name
    ,                        !- Number of Cells
    ,                        !- Cell Control
    ,                        !- Cell Minimum  Water Flow Rate Fraction
    ,                        !- Cell Maximum Water Flow Rate Fraction
    0.5;                     !- Sizing Factor

CoolingTower:TwoSpeed,
    coolingtower2,           !- Name
    coolingtower2 CndW Inlet,!- Water Inlet Node Name
    coolingtower2 CndW Outlet,  !- Water Outlet Node Name
    autosize,                !- Design Water Flow Rate {m3/s}
    autosize,                !- High Fan Speed Air Flow Rate {m3/s}
    autosize,                !- High Fan Speed Fan Power {W}
    autosize,                !- High Fan Speed U-Factor Times Area Value {W/K}
    autocalculate,           !- Low Fan Speed Air Flow Rate {m3/s}
    ,                        !- Low Fan Speed Air Flow Rate Sizing Factor
    autocalculate,           !- Low Fan Speed Fan Power {W}
    ,                        !- Low Fan Speed Fan Power Sizing Factor
    autocalculate,           !- Low Fan Speed U-Factor Times Area Value {W/K}
    ,                        !- Low Fan Speed U-Factor Times Area Sizing Factor
    autocalculate,           !- Free Convection Regime Air Flow Rate {m3/s}
    ,                        !- Free Convection Regime Air Flow Rate Sizing Factor
    autocalculate,           !- Free Convection Regime U-Factor Times Area Value {W/K}
    ,                        !- Free Convection U-Factor Times Area Value Sizing Factor
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    ,                        !- Heat Rejection Capacity and Nominal Capacity Sizing Ratio
    ,                        !- High Speed Nominal Capacity {W}
    autocalculate,           !- Low Speed Nominal Capacity {W}
    ,                        !- Low Speed Nominal Capacity Sizing Factor
    autocalculate,           !- Free Convection Nominal Capacity {W}
    ,                        !- Free Convection Nominal Capacity Sizing Factor
    ,                        !- Design Inlet Air Dry-Bulb Temperature {C}
    ,                        !- Design Inlet Air Wet-Bulb Temperature {C}
    ,                        !- Design Approach Temperature {deltaC}
    ,                        !- Design Range Temperature {deltaC}
    ,                        !- Basin Heater Capacity {W/K}
    ,                        !- Basin Heater Setpoint Temperature {C}
    ,                        !- Basin Heater Operating Schedule Name
    SaturatedExit,           !- Evaporation Loss Mode
    ,                        !- Evaporation Loss Factor {percent/K}
    0.008,                   !- Drift Loss Percent {percent}
    ConcentrationRatio,      !- Blowdown Calculation Mode
    3,                       !- Blowdown Concentration Ratio
    ,                        !- Blowdown Makeup Water Usage Schedule Name
    ,                        !- Supply Water Storage Tank Name
    coolingtower2 Cooling Tower Outdoor Air Inlet Node,  !- Outdoor Air Inlet Node Name
    ,                        !- Number of Cells
    ,                        !- Cell Control
    ,                        !- Cell Minimum  Water Flow Rate Fraction
    ,                        !- Cell Maximum Water Flow Rate Fraction
    0.5;                     !- Sizing Factor

CondenserLoop Coincident sizing is larger than NonCoincident sizing

My model is the same as this post, but let me post a different question.

I have a problem with Coincident plant sizing for CondenserLoop. I tried both Coincident sizing and NonCoincident sizing, but the weird thing is that the autosized condenser loop (Cooling towers and condenser water pumps) by Coincident sizing is much larger than that by NonCoincident sizing. It does not happen in PlantLoop (chillers and chilled water pumps). I think my Coincident sizing settings are appropriate.

Below are the sizing results of cooling towers. Autosized condenser water flow rate by Coincndent sizing is 0.164097m3/s, which is more than 2 times larger than the autosized condenser water flow rate of 0.072678m3/s by NonCoincident sizing. Does anyone know why?

image description

I think the "Initial" values in the html file are the correct ones which are autosized by Coincident sizing. The "Design" values are incorrect. However, this is not just a reporting issue. I also ran annual simulations. The pump end use with Coincident sizing became much larger than that with NonCoincident sizing NonCoincident sizing. EnergyPlus uses the "Design" values.

image description

Is this a bug? Or am I missing something? My settings related to Coincident sizing are as follows. Any suggestions would be appreciated.

    SimulationControl,
        Yes,                     !- Do Zone Sizing Calculation
        Yes,                     !- Do System Sizing Calculation
        Yes,                     !- Do Plant Sizing Calculation
        Yes,                     !- Run Simulation for Sizing Periods
        No,                      !- Run Simulation for Weather File Run Periods
        Yes,                     !- Do HVAC Sizing Simulation for Sizing Periods
        1;                       !- Maximum Number of HVAC Sizing Simulation Passes

    Sizing:Parameters,
        1.25,                    !- Heating Sizing Factor
        1.15;                    !- Cooling Sizing Factor

    Sizing:System,
        VAV_3,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

    Sizing:System,
        VAV_2,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

    Sizing:System,
        VAV_1,                   !- AirLoop Name
        Sensible,                !- Type of Load to Size On
        autosize,                !- Design Outdoor Air Flow Rate {m3/s}
        autosize,                !- Central Heating Maximum System Air Flow Ratio
        30,                      !- Preheat Design Temperature {C}
        0.0033,                  !- Preheat Design Humidity Ratio {kgWater/kgDryAir}
        11,                      !- Precool Design Temperature {C}
        0.008,                   !- Precool Design Humidity Ratio {kgWater/kgDryAir}
        15,                      !- Central Cooling Design Supply Air Temperature {C}
        22,                      !- Central Heating Design Supply Air Temperature {C}
        Coincident,              !- Type of Zone Sum to Use
        No,                      !- 100% Outdoor Air in Cooling
        No,                      !- 100% Outdoor Air in Heating
        0.008,                   !- Central Cooling Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        0.008,                   !- Central Heating Design Supply Air Humidity Ratio {kgWater/kgDryAir}
        DesignDay,               !- Cooling Supply Air Flow Rate Method
        0,                       !- Cooling Supply Air Flow Rate {m3/s}
        ,                        !- Cooling Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Cooling Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Cooling Supply Air Flow Rate Per Unit Cooling Capacity {m3/s-W}
        DesignDay,               !- Heating Supply Air Flow Rate Method
        0,                       !- Heating Supply Air Flow Rate {m3/s}
        ,                        !- Heating Supply Air Flow Rate Per Floor Area {m3/s-m2}
        ,                        !- Heating Fraction of Autosized Heating Supply Air Flow Rate
        ,                        !- Heating Fraction of Autosized Cooling Supply Air Flow Rate
        ,                        !- Heating Supply Air Flow Rate Per Unit Heating Capacity {m3/s-W}
        ZoneSum,                 !- System Outdoor Air Method
        1.0,                     !- Zone Maximum Outdoor Air Fraction {dimensionless}
        CoolingDesignCapacity,   !- Cooling Design Capacity Method
        autosize,                !- Cooling Design Capacity {W}
        ,                        !- Cooling Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Cooling Design Capacity
        HeatingDesignCapacity,   !- Heating Design Capacity Method
        autosize,                !- Heating Design Capacity {W}
        ,                        !- Heating Design Capacity Per Floor Area {W/m2}
        ,                        !- Fraction of Autosized Heating Design Capacity
        VAV;                     !- Central Cooling Capacity Control Method

Sizing:Plant,
    CHWloop Chilled Water Loop,  !- Plant or Condenser Loop Name
    Cooling,                 !- Loop Type
    6.7,                     !- Design Loop Exit Temperature {C}
    6.3,                     !- Loop Design Temperature Difference {deltaC}
    Coincident,              !- Sizing Option
    ,                        !- Zone Timesteps in Averaging Window
    None;                    !- Coincident Sizing Factor Mode

Sizing:Plant,
    CHWloop Condenser Water Loop,  !- Plant or Condenser Loop Name
    Condenser,               !- Loop Type
    29,                      !- Design Loop Exit Temperature {C}
    5.6,                     !- Loop Design Temperature Difference {deltaC}
    Coincident,              !- Sizing Option
    ,                        !- Zone Timesteps in Averaging Window
    None;                    !- Coincident Sizing Factor Mode

CoolingTower:TwoSpeed,
    coolingtower1,           !- Name
    coolingtower1 CndW Inlet,!- Water Inlet Node Name
    coolingtower1 CndW Outlet,  !- Water Outlet Node Name
    autosize,                !- Design Water Flow Rate {m3/s}
    autosize,                !- High Fan Speed Air Flow Rate {m3/s}
    autosize,                !- High Fan Speed Fan Power {W}
    autosize,                !- High Fan Speed U-Factor Times Area Value {W/K}
    autocalculate,           !- Low Fan Speed Air Flow Rate {m3/s}
    ,                        !- Low Fan Speed Air Flow Rate Sizing Factor
    autocalculate,           !- Low Fan Speed Fan Power {W}
    ,                        !- Low Fan Speed Fan Power Sizing Factor
    autocalculate,           !- Low Fan Speed U-Factor Times Area Value {W/K}
    ,                        !- Low Fan Speed U-Factor Times Area Sizing Factor
    autocalculate,           !- Free Convection Regime Air Flow Rate {m3/s}
    ,                        !- Free Convection Regime Air Flow Rate Sizing Factor
    autocalculate,           !- Free Convection Regime U-Factor Times Area Value {W/K}
    ,                        !- Free Convection U-Factor Times Area Value Sizing Factor
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    ,                        !- Heat Rejection Capacity and Nominal Capacity Sizing Ratio
    ,                        !- High Speed Nominal Capacity {W}
    autocalculate,           !- Low Speed Nominal Capacity {W}
    ,                        !- Low Speed Nominal Capacity Sizing Factor
    autocalculate,           !- Free Convection Nominal Capacity {W}
    ,                        !- Free Convection Nominal Capacity Sizing Factor
    ,                        !- Design Inlet Air Dry-Bulb Temperature {C}
    ,                        !- Design Inlet Air Wet-Bulb Temperature {C}
    ,                        !- Design Approach Temperature {deltaC}
    ,                        !- Design Range Temperature {deltaC}
    ,                        !- Basin Heater Capacity {W/K}
    ,                        !- Basin Heater Setpoint Temperature {C}
    ,                        !- Basin Heater Operating Schedule Name
    SaturatedExit,           !- Evaporation Loss Mode
    ,                        !- Evaporation Loss Factor {percent/K}
    0.008,                   !- Drift Loss Percent {percent}
    ConcentrationRatio,      !- Blowdown Calculation Mode
    3,                       !- Blowdown Concentration Ratio
    ,                        !- Blowdown Makeup Water Usage Schedule Name
    ,                        !- Supply Water Storage Tank Name
    coolingtower1 Cooling Tower Outdoor Air Inlet Node,  !- Outdoor Air Inlet Node Name
    ,                        !- Number of Cells
    ,                        !- Cell Control
    ,                        !- Cell Minimum  Water Flow Rate Fraction
    ,                        !- Cell Maximum Water Flow Rate Fraction
    0.5;                     !- Sizing Factor

CoolingTower:TwoSpeed,
    coolingtower2,           !- Name
    coolingtower2 CndW Inlet,!- Water Inlet Node Name
    coolingtower2 CndW Outlet,  !- Water Outlet Node Name
    autosize,                !- Design Water Flow Rate {m3/s}
    autosize,                !- High Fan Speed Air Flow Rate {m3/s}
    autosize,                !- High Fan Speed Fan Power {W}
    autosize,                !- High Fan Speed U-Factor Times Area Value {W/K}
    autocalculate,           !- Low Fan Speed Air Flow Rate {m3/s}
    ,                        !- Low Fan Speed Air Flow Rate Sizing Factor
    autocalculate,           !- Low Fan Speed Fan Power {W}
    ,                        !- Low Fan Speed Fan Power Sizing Factor
    autocalculate,           !- Low Fan Speed U-Factor Times Area Value {W/K}
    ,                        !- Low Fan Speed U-Factor Times Area Sizing Factor
    autocalculate,           !- Free Convection Regime Air Flow Rate {m3/s}
    ,                        !- Free Convection Regime Air Flow Rate Sizing Factor
    autocalculate,           !- Free Convection Regime U-Factor Times Area Value {W/K}
    ,                        !- Free Convection U-Factor Times Area Value Sizing Factor
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    ,                        !- Heat Rejection Capacity and Nominal Capacity Sizing Ratio
    ,                        !- High Speed Nominal Capacity {W}
    autocalculate,           !- Low Speed Nominal Capacity {W}
    ,                        !- Low Speed Nominal Capacity Sizing Factor
    autocalculate,           !- Free Convection Nominal Capacity {W}
    ,                        !- Free Convection Nominal Capacity Sizing Factor
    ,                        !- Design Inlet Air Dry-Bulb Temperature {C}
    ,                        !- Design Inlet Air Wet-Bulb Temperature {C}
    ,                        !- Design Approach Temperature {deltaC}
    ,                        !- Design Range Temperature {deltaC}
    ,                        !- Basin Heater Capacity {W/K}
    ,                        !- Basin Heater Setpoint Temperature {C}
    ,                        !- Basin Heater Operating Schedule Name
    SaturatedExit,           !- Evaporation Loss Mode
    ,                        !- Evaporation Loss Factor {percent/K}
    0.008,                   !- Drift Loss Percent {percent}
    ConcentrationRatio,      !- Blowdown Calculation Mode
    3,                       !- Blowdown Concentration Ratio
    ,                        !- Blowdown Makeup Water Usage Schedule Name
    ,                        !- Supply Water Storage Tank Name
    coolingtower2 Cooling Tower Outdoor Air Inlet Node,  !- Outdoor Air Inlet Node Name
    ,                        !- Number of Cells
    ,                        !- Cell Control
    ,                        !- Cell Minimum  Water Flow Rate Fraction
    ,                        !- Cell Maximum Water Flow Rate Fraction
    0.5;                     !- Sizing Factor