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How to overwrite the terminal box airflow

I found a couple of questions asked in this category, but not sure anyone has actually sucessfully overwrite the airflow using the EMS, AirTerminal:SingleDuct:Uncontrolled, or it must be using a AirTerminal:SingleDuct:Userdefined?

This EMS just doesn't work, not sure why? Any suggestions are highly appreciated.

EnergyManagementSystem:Sensor,
    ZoneTA,                     !- Name
    Core_ZN,             !- Output:Variable or Output:Meter Index Key Name
    Zone Air Temperature;  !- Output:Variable or Output:Meter Name

 EnergyManagementSystem:Actuator,  ! Check EMS manual Page 34
     CoreZoneAirFlow,    !- Name
     CORE_ZN DIRECT AIR, !- Actuated Component Unique Name
     AirTerminal:SingleDuct:Uncontrolled,        !- Actuated Component Type
     Mass Flow Rate;          !- Actuated Component Control Type    

EnergyManagementSystem:ProgramCallingManager,
    ZoneAirFlow_Overwrite Manager,  !- Name
    BeginTimestepBeforePredictor,  !- EnergyPlus Model Calling Point
    ZoneAirFlow_Overwrite;  !- Program Name 1

EnergyManagementSystem:Program,
    ZoneAirFlow_Overwrite,  !- Name
    IF ZoneTA>23,  !- Program Line 1
    SET CoreZoneAirFlow = 0.2,  !- Program Line 2
    ELSE,                    !- <none>
    SET CoreZoneAirFlow = NULL,  !- <none>
    ENDIF;                   !- <none>

How to overwrite the terminal box airflow

I found a couple of questions asked in this category, but not sure anyone has actually sucessfully overwrite the airflow using the EMS, AirTerminal:SingleDuct:Uncontrolled, or it must be using a AirTerminal:SingleDuct:Userdefined?

This EMS just doesn't work, not sure why? Any suggestions are highly appreciated.

EnergyManagementSystem:Sensor,
    ZoneTA,                     !- Name
    Core_ZN,             !- Output:Variable or Output:Meter Index Key Name
    Zone Air Temperature;  !- Output:Variable or Output:Meter Name

 EnergyManagementSystem:Actuator,  ! Check EMS manual Page 34
     CoreZoneAirFlow,    !- Name
     CORE_ZN DIRECT AIR, !- Actuated Component Unique Name
     AirTerminal:SingleDuct:Uncontrolled,        !- Actuated Component Type
     Mass Flow Rate;          !- Actuated Component Control Type    

EnergyManagementSystem:ProgramCallingManager,
    ZoneAirFlow_Overwrite Manager,  !- Name
    BeginTimestepBeforePredictor,  !- EnergyPlus Model Calling Point
    ZoneAirFlow_Overwrite;  !- Program Name 1

EnergyManagementSystem:Program,
    ZoneAirFlow_Overwrite,  !- Name
    IF ZoneTA>23,  !- Program Line 1
    SET CoreZoneAirFlow = 0.2,  !- Program Line 2
    ELSE,                    !- <none>
    SET CoreZoneAirFlow = NULL,  !- <none>
    ENDIF;                   !- <none>

How to overwrite the terminal box airflow

I found a couple of questions asked in this category, but not sure anyone has actually sucessfully overwrite the airflow using the EMS, AirTerminal:SingleDuct:Uncontrolled, or it must be using a AirTerminal:SingleDuct:Userdefined?

This EMS just doesn't work, not sure why? Any suggestions are highly appreciated.

EnergyManagementSystem:Sensor,
    ZoneTA,                     !- Name
    Core_ZN,             !- Output:Variable or Output:Meter Index Key Name
    Zone Air Temperature;  !- Output:Variable or Output:Meter Name

 EnergyManagementSystem:Actuator,  ! Check EMS manual Page 34
     CoreZoneAirFlow,    !- Name
     CORE_ZN DIRECT AIR, !- Actuated Component Unique Name
     AirTerminal:SingleDuct:Uncontrolled,        !- Actuated Component Type
     Mass Flow Rate;          !- Actuated Component Control Type    

EnergyManagementSystem:ProgramCallingManager,
    ZoneAirFlow_Overwrite Manager,  !- Name
    BeginTimestepBeforePredictor,  !- EnergyPlus Model Calling Point
    ZoneAirFlow_Overwrite;  !- Program Name 1

EnergyManagementSystem:Program,
    ZoneAirFlow_Overwrite,  !- Name
    IF ZoneTA>23,  !- Program Line 1
    SET CoreZoneAirFlow = 0.2,  !- Program Line 2
    ELSE,                    !- <none>
    SET CoreZoneAirFlow = NULL,  !- <none>
    ENDIF;                   !- <none>

Updated:

Now it switched a Userdefined Air terminal units with reheat coil. The reheat coil is not user defined. The airflow can be override, but the reheat coil seems to have connection issues.

AirTerminal:SingleDuct:UserDefined,
    Core_ZN VAV Reheat,      !- Name
    CORE_ZN ATU Sim Programs,!- Overall Model Simulation Program Calling Manager Name
    CORE_ZN ATU Init Programs,  !- Model Setup and Sizing Program Calling Manager Name
    Core_ZN Zone Equip Inlet,!- Primary Air Inlet Node Name
    Core_ZN Supply Inlet,    !- Primary Air Outlet Node Name
    ,                        !- Secondary Air Inlet Node Name
    ,                        !- Secondary Air Outlet Node Name
    1,                       !- Number of Plant Loop Connections
    Core_ZN Reheat Coil HW Inlet,  !- Plant Connection 1 Inlet Node Name
    Core_ZN Reheat Coil HW Outlet;  !- Plant Connection 1 Outlet Node Name

Coil:Heating:Water,
    Core_ZN Reheat Coil,     !- Name
    HVACOperationSchd,       !- Availability Schedule Name
    autosize,                !- U-Factor Times Area Value {W/K}
    autosize,                !- Maximum Water Flow Rate {m3/s}
    Core_ZN Reheat Coil HW Inlet,  !- Water Inlet Node Name
    Core_ZN Reheat Coil HW Outlet,  !- Water Outlet Node Name
    Core_ZN Zone Equip Inlet,   !- Air Inlet Node Name
    Core_ZN Supply Inlet,    !- Air Outlet Node Name
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    autosize,                !- Rated Capacity {W}
    82.2,                    !- Rated Inlet Water Temperature {C}
    16.6,                    !- Rated Inlet Air Temperature {C}
    71.1,                    !- Rated Outlet Water Temperature {C}
    32.2,                    !- Rated Outlet Air Temperature {C}
    1.0;                     !- Rated Ratio for Air and Water Convection

 Branch,
    Core_ZN Reheat Coil HW Branch,  !- Name
    ,                        !- Maximum Flow Rate {m3/s}
    ,                        !- Pressure Drop Curve Name
    AirTerminal:SingleDuct:UserDefined,  !- Component 1 Object Type
    Core_ZN VAV Reheat,      !- Component 1 Name
    Core_ZN Reheat Coil HW Inlet,  !- Component 1 Inlet Node Name
    Core_ZN Reheat Coil HW Outlet,  !- Component 1 Outlet Node Name
    Active;                  !- Component 1 Branch Control Type

The EMS programs are ignored here. In this case, the coil connection parts have some errors. Please see below.

* Severe * Node Connection Error, Node="CORE_ZN ZONE EQUIP INLET", The same node appears as a non-parent Inlet node more than once. * ~~~ * Reference Object=AIRTERMINAL:SINGLEDUCT:USERDEFINED, Name=CORE_ZN VAV REHEAT * ~~~ * Reference Object=COIL:HEATING:WATER, Name=CORE_ZN REHEAT COIL * Severe * Node Connection Error, Node="CORE_ZN REHEAT COIL HW INLET", The same node appears as a non-parent Inlet node more than once. * ~~~ * Reference Object=AIRTERMINAL:SINGLEDUCT:USERDEFINED, Name=CORE_ZN VAV REHEAT * ~~~ * Reference Object=COIL:HEATING:WATER, Name=CORE_ZN REHEAT COIL * Severe * Node Connection Error, Node="CORE_ZN SUPPLY INLET", The same node appears as a non-parent Outlet node more than once. * ~~~ * Reference Object=AIRTERMINAL:SINGLEDUCT:USERDEFINED, Name=CORE_ZN VAV REHEAT * ~~~ * Reference Object=COIL:HEATING:WATER, Name=CORE_ZN REHEAT COIL * Severe * Node Connection Error, Node="CORE_ZN REHEAT COIL HW OUTLET", The same node appears as a non-parent Outlet node more than once. * ~~~ * Reference Object=AIRTERMINAL:SINGLEDUCT:USERDEFINED, Name=CORE_ZN VAV REHEAT * ~~~ * Reference Object=COIL:HEATING:WATER, Name=CORE_ZN REHEAT COIL

How to overwrite the terminal box airflow

I found a couple of questions asked in this category, but not sure anyone has actually sucessfully overwrite the airflow using the EMS, AirTerminal:SingleDuct:Uncontrolled, or it must be using a AirTerminal:SingleDuct:Userdefined?

This EMS just doesn't work, not sure why? Any suggestions are highly appreciated.


EnergyManagementSystem:Sensor,
    ZoneTA,                     !- Name
    Core_ZN,             !- Output:Variable or Output:Meter Index Key Name
    Zone Air Temperature;  !- Output:Variable or Output:Meter Name

 EnergyManagementSystem:Actuator,  ! Check EMS manual Page 34
     CoreZoneAirFlow,    !- Name
     CORE_ZN DIRECT AIR, !- Actuated Component Unique Name
     AirTerminal:SingleDuct:Uncontrolled,        !- Actuated Component Type
     Mass Flow Rate;          !- Actuated Component Control Type    

EnergyManagementSystem:ProgramCallingManager,
    ZoneAirFlow_Overwrite Manager,  !- Name
    BeginTimestepBeforePredictor,  !- EnergyPlus Model Calling Point
    ZoneAirFlow_Overwrite;  !- Program Name 1

EnergyManagementSystem:Program,
    ZoneAirFlow_Overwrite,  !- Name
    IF ZoneTA>23,  !- Program Line 1
    SET CoreZoneAirFlow = 0.2,  !- Program Line 2
    ELSE,                    !- <none>
    SET CoreZoneAirFlow = NULL,  !- <none>
    ENDIF;                   !- <none>

Updated:

Now it switched a Userdefined Air terminal units with reheat coil. The reheat coil is not user defined. The airflow can be override, but the reheat coil seems to have connection issues.

AirTerminal:SingleDuct:UserDefined,
    Core_ZN VAV Reheat,      !- Name
    CORE_ZN ATU Sim Programs,!- Overall Model Simulation Program Calling Manager Name
    CORE_ZN ATU Init Programs,  !- Model Setup and Sizing Program Calling Manager Name
    Core_ZN Zone Equip Inlet,!- Primary Air Inlet Node Name
    Core_ZN Supply Inlet,    !- Primary Air Outlet Node Name
    ,                        !- Secondary Air Inlet Node Name
    ,                        !- Secondary Air Outlet Node Name
    1,                       !- Number of Plant Loop Connections
    Core_ZN Reheat Coil HW Inlet,  !- Plant Connection 1 Inlet Node Name
    Core_ZN Reheat Coil HW Outlet;  !- Plant Connection 1 Outlet Node Name

Coil:Heating:Water,
    Core_ZN Reheat Coil,     !- Name
    HVACOperationSchd,       !- Availability Schedule Name
    autosize,                !- U-Factor Times Area Value {W/K}
    autosize,                !- Maximum Water Flow Rate {m3/s}
    Core_ZN Reheat Coil HW Inlet,  !- Water Inlet Node Name
    Core_ZN Reheat Coil HW Outlet,  !- Water Outlet Node Name
    Core_ZN Zone Equip Inlet,   !- Air Inlet Node Name
    Core_ZN Supply Inlet,    !- Air Outlet Node Name
    UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
    autosize,                !- Rated Capacity {W}
    82.2,                    !- Rated Inlet Water Temperature {C}
    16.6,                    !- Rated Inlet Air Temperature {C}
    71.1,                    !- Rated Outlet Water Temperature {C}
    32.2,                    !- Rated Outlet Air Temperature {C}
    1.0;                     !- Rated Ratio for Air and Water Convection

 Branch,
    Core_ZN Reheat Coil HW Branch,  !- Name
    ,                        !- Maximum Flow Rate {m3/s}
    ,                        !- Pressure Drop Curve Name
    AirTerminal:SingleDuct:UserDefined,  !- Component 1 Object Type
    Core_ZN VAV Reheat,      !- Component 1 Name
    Core_ZN Reheat Coil HW Inlet,  !- Component 1 Inlet Node Name
    Core_ZN Reheat Coil HW Outlet,  !- Component 1 Outlet Node Name
    Active;                  !- Component 1 Branch Control Type

The EMS programs are ignored here. In this case, the coil connection parts have some errors. Please see below.

* Severe * Node Connection Error, Node="CORE_ZN ZONE EQUIP INLET", The same node appears as a non-parent Inlet node more than once. * ~~~ * Reference Object=AIRTERMINAL:SINGLEDUCT:USERDEFINED, Name=CORE_ZN VAV REHEAT * ~~~ * Reference Object=COIL:HEATING:WATER, Name=CORE_ZN REHEAT COIL * Severe * Node Connection Error, Node="CORE_ZN REHEAT COIL HW INLET", The same node appears as a non-parent Inlet node more than once. * ~~~ * Reference Object=AIRTERMINAL:SINGLEDUCT:USERDEFINED, Name=CORE_ZN VAV REHEAT * ~~~ * Reference Object=COIL:HEATING:WATER, Name=CORE_ZN REHEAT COIL * Severe * Node Connection Error, Node="CORE_ZN SUPPLY INLET", The same node appears as a non-parent Outlet node more than once. * ~~~ * Reference Object=AIRTERMINAL:SINGLEDUCT:USERDEFINED, Name=CORE_ZN VAV REHEAT * ~~~ * Reference Object=COIL:HEATING:WATER, Name=CORE_ZN REHEAT COIL * Severe * Node Connection Error, Node="CORE_ZN REHEAT COIL HW OUTLET", The same node appears as a non-parent Outlet node more than once. * ~~~ * Reference Object=AIRTERMINAL:SINGLEDUCT:USERDEFINED, Name=CORE_ZN VAV REHEAT * ~~~ * Reference Object=COIL:HEATING:WATER, Name=CORE_ZN REHEAT COIL