[EnergyPlus_Support] Re: How to set up a Coil:Heating:Water object in a CAV system to controls?

["FrancescoP" <direzionecontraria@xxxxxxxx>]

I have to model system 3 of ASHRAE 90.1-2007 (PSZ-AC, i.e. Packaged rooftop air conditioner, fan: constant volume, cooling type: direct expansion, heating type: district heat). Every AHU is connected to one zone or to two zones that have similar conditions. In some zones I have to model a constant fresh (outdoor) air flow during occupied hours. Therefore for those zones air flow is already determined. To control temperatures in those zone the temperature of supply air shall change in order to meet the heat requirements hour by hour. Here a part of my model:

AirLoopHVAC:ControllerList,
    uta 28massaggi1 Controllers,  !- Name
    Controller:WaterCoil,    !- Controller 1 Object Type
    uta 28massaggi1 AHU/1  Heating Coil Controller;  !- Controller 1 Name

Controller:WaterCoil,
    uta 28massaggi1 AHU/1  Heating Coil Controller,  !- Name
    Temperature,             !- Control Variable
    Normal,                  !- Action
    Flow,                    !- Actuator Variable
    uta 28massaggi1 Supply Side Outlet 1,  !- Sensor Node Name
    uta 28massaggi1 AHU/1  Heating Coil Water Inlet Node,  !- Actuator Node Name
    autosize,                !- Controller Convergence Tolerance {deltaC}
    autosize,                !- Maximum Actuated Flow {m3/s}
    0.000;                   !- Minimum Actuated Flow {m3/s}

SetpointManager:SingleZone:Heating,
    sm 28massaggi1 H,        !- Name
    Temperature,             !- Control Variable
    5,                       !- Minimum Supply Air Temperature {C}
    80,                      !- Maximum Supply Air Temperature {C}
    00interrato:28massaggi1, !- Control Zone Name
    00interrato:28massaggi1 Zone Air Node,  !- Zone Node Name
    uta 28massaggi1 Zone Splitter/1 Outlet Node 1,  !- Zone Inlet Node Name
    uta 28massaggi1 Supply Side Outlet 1;  !- Setpoint Node or NodeList Name

ZoneControl:Thermostat,
    00interrato:28massaggi1 Thermostat,  !- Name
    00interrato:28massaggi1, !- Zone or ZoneList Name
    48,                      !- Control Type Schedule Name
    ThermostatSetpoint:DualSetpoint,  !- Control 1 Object Type
    00interrato:28massaggi1 Dual SP;  !- Control 1 Name

ThermostatSetpoint:DualSetpoint,
    00interrato:28massaggi1 Dual SP,  !- Name
    I28,                     !- Heating Setpoint Temperature Schedule Name
    E90C;                    !- Cooling Setpoint Temperature Schedule Name

The problem is that the zone temperature does not meet the setpoint temperature (during winter it is too cold). Components are autosized. As sizing period one summer day and one winter day are used (SizingPeriod:DesignDay objects). In some zones also during sizing periods setpoint temperatures are not met. No reheat coils exist.
Any advice, please? 
I see that this discussion focused on the same subject, but I am not able to find a solution.
With Regards
Francesco Passerini


--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "Ke Xu" <xukevin24@...> wrote:
>
> Dear all,
> I am simulating a constant air volume system with a hot-water heating coil in the air-loop, and I am trying to set up controls for coil to maintain supply air temperature set point calculated to maintain the zone temperature. the objects I am using include "Coil: Heating: Water", "Controller: WaterCoil" and "SetpointManager:SingZone:Heating". Somehow, it doesn't work as I expected, the zone temperature in winter time can't be maintained. Any help and comments are appreciated. Thanks in advance.
> 
> --Ke
> 
> Part of my model related with heating coil is shown below:
> 
> Coil:Heating:Water,
>     PSZ_1:1_HEATC,           !- Name
>     Always_On,               !- Availability Schedule Name
>     Autosize,                !- U-Factor Times Area Value {W/K}
>     Autosize,                !- Maximum Water Flow Rate {m3/s}
>     PSZ_1:1 HeatingCoilWaterInlet,  !- Water Inlet Node Name
>     PSZ_1:1 HeatingCoilWaterOutlet,  !- Water Outlet Node Name
>     PSZ_1:1_CoolC-PSZ_1:1_HeatCNode,  !- Air Inlet Node Name
>     PSZ_1:1_HeatC-PSZ_1:1_FanNode,  !- Air Outlet Node Name
>     UFactorTimesAreaAndDesignWaterFlowRate,  !- Performance Input Method
>     Autosize,                !- Rated Capacity {W}
>     82.2222222222222,        !- Rated Inlet Water Temperature {C}
>     12.7777781162733,        !- Rated Inlet Air Temperature {C}
>     71.1111111111111,        !- Rated Outlet Water Temperature {C}
>     43.3333333333334,        !- Rated Outlet Air Temperature {C}
>     0.5;                     !- Rated Ratio for Air and Water Convection
> 
> Controller:WaterCoil,
>     OS:Controller:WaterCoil 1,  !- Name
>     Temperature,             !- Control Variable
>     Normal,                  !- Action
>     Flow,                    !- Actuator Variable
>     PSZ_1:1 Supply Equipment Outlet Node,  !- Sensor Node Name
>     PSZ_1:1 HeatingCoilWaterInlet,  !- Actuator Node Name
>     Autosize,                !- Controller Convergence Tolerance {deltaC}
>     Autosize,                !- Maximum Actuated Flow {m3/s}
>     1e-007;                  !- Minimum Actuated Flow {m3/s}
> 
> SetpointManager:SingleZone:Heating,
>     SupAirTemp MngrCore_bottom,  !- Name
>     Temperature,             !- Control Variable
>     10.0,                    !- Minimum Supply Air Temperature {C}
>     43.3333344812747,        !- Maximum Supply Air Temperature {C}
>     Core_bottom,             !- Control Zone Name
>     Core_bottom Air Node,    !- Zone Node Name
>     Core_bottom Direct Air Inlet Node Name,  !- Zone Inlet Node Name
>     PSZ_1:1 Supply Equipment Outlet Node;  !- Setpoint Node or NodeList Name
>



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