Natural ventilation to reduce cooling loads

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I'm modeling a very simple house with a single thermal zone with CAV DX coil cooling with a single air duct. In order to test cooling loads reduction with window opening, I constructed a simple AFN for natural ventilation, using NoMultizoneOr Distribution and Surface Average Calculation method (I am a novice to Airflownetwork (AFN) though).

However, even though the AFN is set, I find no change in cooling loads. Can anyone explain why? and how to fix this problem? Thanks in advance. My inputs are as follows:

!-   ===========  ALL OBJECTS IN CLASS: AIRFLOWNETWORK:SIMULATIONCONTROL ===========

AirflowNetwork:SimulationControl,

    EllisAirNetwork,         !- Name
    NoMultizoneOrDistribution,  !- AirflowNetwork Control
    SurfaceAverageCalculation,  !- Wind Pressure Coefficient Type
    ,                        !- AirflowNetwork Wind Pressure Coefficient Array Name
    ,                        !- Height Selection for Local Wind Speed Calculation
    LowRise,                 !- Building Type
    500,                     !- Maximum Number of Iterations {dimensionless}
    LinearInitializationMethod,  !- Initialization Type
    0.0001,                  !- Relative Airflow Convergence Tolerance {dimensionless}
    0.000001,                !- Absolute Airflow Convergence Tolerance {kg/s}
    -.5,                     !- Convergence Acceleration Limit {dimensionless}
    90,                      !- Azimuth Angle of Long Axis of Building {deg}
    0.95;                    !- Ratio of Building Width Along Short Axis to Width Along Long Axis


!-   ===========  ALL OBJECTS IN CLASS: AIRFLOWNETWORK:MULTIZONE:ZONE ===========

AirflowNetwork:MultiZone:Zone,

    Thermal Zone 1,          !- Zone Name
    Constant,                !- Ventilation Control Mode
    Ellis House ClgSetp 1,   !- Ventilation Control Zone Temperature Setpoint Schedule Name
    0.5,                     !- Minimum Venting Open Factor {dimensionless}
    3,                       !- Indoor and Outdoor Temperature Difference Lower Limit For Maximum Venting Open Factor {deltaC}
    10,                      !- Indoor and Outdoor Temperature Difference Upper Limit for Minimun Venting Open Factor {deltaC}
    0.0,                     !- Indoor and Outdoor Enthalpy Difference Lower Limit For Maximum Venting Open Factor {deltaJ/kg}
    300000.0;                !- Indoor and Outdoor Enthalpy Difference Upper Limit for Minimun Venting Open Factor {deltaJ/kg}


!-   ===========  ALL OBJECTS IN CLASS: AIRFLOWNETWORK:MULTIZONE:SURFACE ===========

AirflowNetwork:MultiZone:Surface,

    Sub Surface 1,           !- Surface Name
    VentOpening,             !- Leakage Component Name
    Sfacade,                 !- External Node Name
    0.6,                     !- Window/Door Opening Factor, or Crack Factor {dimensionless}
    Constant,                !- Ventilation Control Mode
    ,                        !- Ventilation Control Zone Temperature Setpoint Schedule Name
    0.1,                     !- Minimum Venting Open Factor {dimensionless}
    2,                       !- Indoor and Outdoor Temperature Difference Lower Limit For Maximum Venting Open Factor {deltaC}
    3,                       !- Indoor and Outdoor Temperature Difference Upper Limit for Minimun Venting Open Factor {deltaC}
    ,                        !- Indoor and Outdoor Enthalpy Difference Lower Limit For Maximum Venting Open Factor {deltaJ/kg}
    300000,                  !- Indoor and Outdoor Enthalpy Difference Upper Limit for Minimun Venting Open Factor {deltaJ/kg}
    Always On;               !- Venting Availability Schedule Name

AirflowNetwork:MultiZone:Surface,

    Sub Surface 4,           !- Surface Name
    VentOpening,             !- Leakage Component Name
    Nfacade,                 !- External Node Name
    0.4,                     !- Window/Door Opening Factor, or Crack Factor {dimensionless}
    Constant,                !- Ventilation Control Mode
    ,                        !- Ventilation Control Zone Temperature Setpoint Schedule Name
    0.1,                     !- Minimum Venting Open Factor {dimensionless}
    1,                       !- Indoor and Outdoor Temperature Difference Lower Limit For Maximum Venting Open Factor {deltaC}
    3,                       !- Indoor and Outdoor Temperature Difference Upper Limit for Minimun Venting Open Factor {deltaC}
    ,                        !- Indoor and Outdoor Enthalpy Difference Lower Limit For Maximum Venting Open Factor {deltaJ/kg}
    300000,                  !- Indoor and Outdoor Enthalpy Difference Upper Limit for Minimun Venting Open Factor {deltaJ/kg}
    Always On;               !- Venting Availability Schedule Name

!-   ===========  ALL OBJECTS IN CLASS: AIRFLOWNETWORK:MULTIZONE:COMPONENT:SIMPLEOPENING ...