[EnergyPlus_Support] Boiler control through EMS

[<marko.ignjatovic1980@xxxxxxxxx>]

Hi all,

I need help in creating the following hot water boiler control:
- i have a gas condensing boiler with known capacity and design conditions
- boiler has the following control logic:
   While on it measures inlet and outlet temperatures,
   if temperature difference is less than 11K (oC) it turns OFF the burner
   when this difference drops it turns ON the burner
   while on always want to reach constant outlet setpoint of 80oC, it has modulating burner so during start it goes with 100% capacity and afterwards it modulates it up to 20%.
- boiler is accompanied with constant speed pump which is always ON (for a defined schedule of time) and has the flow rate autosized to the value which coincides with the real pump.
- i tried using EMS to switch it ON/OFF but it want turn the boiler on (like, difference is always less than 11)
- when I made simulations without EMS I saw that condition was reached several hundred times during heating season

Here is the EMS code:

!-   ===========  ALL OBJECTS IN CLASS: ENERGYMANAGEMENTSYSTEM:SENSOR ===========

EnergyManagementSystem:Sensor,
    OutsideAirSensor,        !- Name
    Environment,             !- Output:Variable or Output:Meter Index Key Name
    Site Outdoor Air Drybulb Temperature;  !- Output:Variable or Output:Meter Name

EnergyManagementSystem:Sensor,
    BoilerSupply,            !- Name
    HW Supply Outlet Node,   !- Output:Variable or Output:Meter Index Key Name
    System Node Temperature; !- Output:Variable or Output:Meter Name

EnergyManagementSystem:Sensor,
    BoilerReturn,            !- Name
    HW Supply Inlet Node,    !- Output:Variable or Output:Meter Index Key Name
    System Node Temperature; !- Output:Variable or Output:Meter Name


!-   ===========  ALL OBJECTS IN CLASS: ENERGYMANAGEMENTSYSTEM:ACTUATOR ===========

EnergyManagementSystem:Actuator,
    ControlValve2,           !- Name
    BOILER DOSTUPNOST,       !- Actuated Component Unique Name
    Schedule:Compact,        !- Actuated Component Type
    Schedule Value;          !- Actuated Component Control Type


!-   ===========  ALL OBJECTS IN CLASS: ENERGYMANAGEMENTSYSTEM:PROGRAMCALLINGMANAGER ===========

EnergyManagementSystem:ProgramCallingManager,
    BoilerControl,

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