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2021-06-10 21:07:25 -0500 answered a question Does DCV/mechanical ventilation work for occupant count below 1 in EnergyPlus?

The answer is Yes. Occupancy (number of people) does not have to be a whole number. EnergyPlus recognizes a small number

2021-06-10 21:07:25 -0500 received badge  Rapid Responder (source)
2021-06-10 06:46:29 -0500 commented answer Why is my minimum setpoint not met?

@Wolfgang Kaiser so, your problem is overheat, right? What is your HVAC system? Autosize or manual input? If you could s

2021-06-10 03:18:13 -0500 commented answer HVACTemplate:System:VAV Heating Coil Design Setpoint

The sketch was drawn on iPad using an app called "Metamoji Note". It's the best sketching app for me, but it's Japanese

2021-06-10 01:14:24 -0500 received badge  Rapid Responder (source)
2021-06-10 01:14:24 -0500 answered a question Why is my minimum setpoint not met?

15 for heating and 25 for cooling? If so, the result is reasonable. Between 15 and 25 is a deadband (uncontrolled range)

2021-06-09 20:44:55 -0500 edited question How can DCV and VAV be compatible in both heating and cooling?

How can DCV and VAV be compatible in both heating and cooling? Has anyone been able to successfully implement CO2 based

2021-06-09 11:09:55 -0500 received badge  Self-Learner (source)
2021-06-08 03:25:12 -0500 edited answer Modeling a Blind with glazing layer data

I refer to WINDOW, which is the free software that can calculate U-value and other factors for glazing including framing

2021-06-08 02:33:44 -0500 edited answer Modeling a Blind with glazing layer data

I refer to WINDOW, which is the free software that can calculate U-value and other factors for glazing including framing

2021-06-08 01:35:35 -0500 edited answer Modeling a Blind with glazing layer data

I refer to WINDOW, which is the free software that can calculate U-value and other factors for glazing including framing

2021-06-08 01:17:29 -0500 edited answer Modeling a Blind with glazing layer data

I refer to WINDOW, which is the free software that can calculate U-value and other factors for glazing including framing

2021-06-08 01:07:06 -0500 answered a question Modeling a Blind with glazing layer data

I refer to WINDOW, which is the free software that can calculate U-value and other factors for glazing including framing

2021-06-07 12:48:47 -0500 edited answer HVAC energy consumption

Your goal is to calculate the zone bill. Then, firstly, please don't use sensible heating and cooling energy. You should

2021-06-07 12:06:00 -0500 edited answer HVAC energy consumption

Your goal is to calculate the zone bill. Then, firstly, please don't use sensible heating and cooling energy. You should

2021-06-07 11:54:36 -0500 edited answer HVAC energy consumption

Your goal is to calculate the zone bill. Then, firstly, please don't use sensible heating and cooling energy. You should

2021-06-07 11:53:32 -0500 answered a question HVAC energy consumption

Your goal is to calculate the zone bill. Then, firstly, please don't use sensible heating and cooling energy. You should

2021-06-06 06:46:34 -0500 edited question How can DCV and VAV be compatible in both heating and cooling?

How can DCV and VAV be compatible in both heating and cooling? Has anyone been able to successfully implement CO2 based

2021-06-06 06:43:33 -0500 edited question How can DCV and VAV be compatible in both heating and cooling?

How can DCV and VAV be compatible in both heating and cooling? Has anyone been able to successfully implement CO2 based

2021-06-06 06:37:48 -0500 edited question How can DCV and VAV be compatible in both heating and cooling?

How can DCV and VAV be compatible in both heating and cooling? Has anyone been able to successfully implement CO2 based

2021-06-06 06:34:21 -0500 asked a question How can DCV and VAV be compatible in both heating and cooling?

How can DCV and VAV be compatible in both heating and cooling? Has anyone been able to successfully implement CO2 based

2021-06-06 00:02:51 -0500 edited answer How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

After hundreds of trials and errors, I came up with a very simple answer. Inputting the specific OA flow rate (i.e., 0.

2021-06-04 13:05:01 -0500 commented question How is Demand Controlled Ventilation applied without a Controller:MechanicalVentilation object?

I did the same way (updated to v9.0 and plotted Air System Outdoor Air Mass Flow Rate), but I got the completely differe

2021-06-02 21:49:44 -0500 answered a question How to simulate a variable-speed condenser water pump in EnergyPlus?

I was also interested in this problem and tried to solve it, but the current EnergyPlus doesn't allow for variable flow

2021-05-25 08:00:52 -0500 answered a question Cooling useful energy

I'm not sure exactly what your definition of 'the useful energy' is, but the sum of Cooling Coil Total Cooling Rate does

2021-05-22 22:55:06 -0500 answered a question How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

After hundreds of trials and errors, I came up with a very simple answer. Inputting the specific OA flow rate (i.e., 0.

2021-05-22 20:26:48 -0500 edited question How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate? Any model is fine, but let me explain the current issue by us

2021-05-19 08:47:01 -0500 edited answer Secondary Chilled Water Loop Setpoint can't be controlled

Let me supplement the answer from @codybond. Just changing Heat Exchange Model Type from CrossFlowBothUnmixed to Ideal

2021-05-19 06:15:29 -0500 commented answer Secondary Chilled Water Loop Setpoint can't be controlled

@codybond thank you for your advise. I ran the case with everything autosized. In this ExamleFile, chiller capacity and

2021-05-19 06:06:02 -0500 edited answer Secondary Chilled Water Loop Setpoint can't be controlled

Let me supplement the answer from @codybond. Just changing Heat Exchange Model Type from CrossFlowBothUnmixed to Ideal

2021-05-19 06:04:59 -0500 edited answer Secondary Chilled Water Loop Setpoint can't be controlled

Let me supplement the answer from @codybond. Just changing Heat Exchange Model Type from CrossFlowBothUnmixed to Ideal

2021-05-19 05:50:15 -0500 answered a question Secondary Chilled Water Loop Setpoint can't be controlled

Let me supplement the answer from @codybond. Just changing Heat Exchange Model Type from CrossFlowBothUnmixed to Ideal

2021-05-19 05:20:39 -0500 received badge  Commentator
2021-05-19 05:20:39 -0500 commented answer Secondary Chilled Water Loop Setpoint can't be controlled

@codybond thank you for your advise. I ran the case with everything autosized. In this ExamleFile, chiller capacity and

2021-05-15 15:27:07 -0500 asked a question Secondary Chilled Water Loop Setpoint can't be controlled

Secondary Chilled Water Loop Setpoint can't be controlled There is a similar post in the past, but that answer did not t

2021-05-09 21:39:40 -0500 edited answer Control of Ice Storage model with Heat Exchanger

With great help from @szsz, I managed to make my model work, though it's not perfect. Here is the fixed IDF file. Pro

2021-05-09 08:54:59 -0500 marked best answer Control of Ice Storage model with Heat Exchanger

I've been struggling with my ice storage model for a long time, and I've referred to previous posts, but I can't get it to work as expected, so I'd like to ask you how to solve the problems.

Below is a schematic diagram of plant loop and condenser loop of my model. The IDF file is here. Its version is v8.9.0. BrineChiller + IceTank is the main plant system, and BackupChiller is only for assisting when the IceTank is completely discharged and there is still cooling load.

image description

There are two major fatal problems with my current model.

  • Problem 1: ThermalStorage:Ice:Detailed doesn't charge nor discharge at all.
  • Problem 2: Operation Status of HeatExchanger:FluidToFluid is always 0 (off).

About Problem 1, as some previous posts suggest, it seems that we have to use EMS to make the ice storage model work properly. None of ExampleFiles for ice storage model work properly. The charts below are part of the results of the ExampleFiles (they are not the results of my model).

image description

I referred to one thesis “Strategic control and cost optimization of thermal energy storage in buildings using EnergyPlus” and tried to control charge/discharge of Ice Storage in my model based on Ice Thermal Storage End Fraction, but so far it's not working. I'm new to EMS and I think there's something wrong with it. Below is my input to EMS. Now I'm using only On/Off Supervisory. This control type doesn't have the function to force equipment to run. It can only run equipment normally based on other controls. I don't know how to force the Ice Storage to charge/discharge.

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

EnergyManagementSystem:Sensor,
    SensorForIceThermalStorageEndFraction,  !- Name
    IceTank,                 !- Output:Variable or Output:Meter Index Key Name
    Ice Thermal Storage End Fraction ;  !- Output:Variable or Output:Meter Name


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

EnergyManagementSystem:Actuator,
    IceTankOverride,         !- Name
    IceTank,                 !- Actuated Component Unique Name
    Plant Component ThermalStorage:Ice:Detailed,  !- Actuated Component Type
    On/Off Supervisory;      !- Actuated Component Control Type

EnergyManagementSystem:Actuator,
    PHEOverride,             !- Name
    PHE,                     !- Actuated Component Unique Name
    Plant Component HeatExchanger:FluidToFluid,  !- Actuated Component Type
    On/Off Supervisory;      !- Actuated Component Control Type

EnergyManagementSystem:Actuator,
    BackupChillerOverride,   !- Name
    BackupChiller,           !- Actuated Component Unique Name
    Plant Component Chiller:Electric:EIR,  !- Actuated Component Type
    On/Off Supervisory;      !- Actuated Component Control Type

EnergyManagementSystem:Actuator,
    ChPriSupPumpOverride,    !- Name
    ChPriSupPump,            !- Actuated Component Unique Name
    Plant Component Pump:VariableSpeed,  !- Actuated Component Type
    On/Off Supervisory;      !- Actuated Component Control Type

EnergyManagementSystem:Actuator,
    ChPriLoopOverride,       !- Name
    ChPriLoop,               !- Actuated Component Unique Name
    Plant Loop Overall,      !- Actuated Component Type
    On/Off Supervisory;      !- Actuated Component Control Type


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

EnergyManagementSystem:ProgramCallingManager,
    IceTankOnOffManagement,  !- Name
    AfterPredictorBeforeHVACManagers,  !- EnergyPlus Model Calling Point
    EMS_IceTankControlProgram;  !- Program Name 1


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

EnergyManagementSystem:Program,
    EMS_IceTankControlProgram,  !- Name
    IF (Hour >= 23) || (Hour <= 6) && (SensorForIceThermalStorageEndFraction < 0.95),  !- Program Line 1
    SET ChPriLoopOverride = 1.0,  !- Program Line 2
    ELSEIF (Hour >= 23) || (Hour <= 6) && (SensorForIceThermalStorageEndFraction >= 0.95 ...
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2021-05-09 08:51:33 -0500 edited answer Control of Ice Storage model with Heat Exchanger

With great help from @szsz, I managed to make my model work, though it's not perfect. Here is the fixed IDF file. Pro

2021-05-09 08:39:23 -0500 edited question Control of Ice Storage model with Heat Exchanger

Control of Ice Storage model with Heat Exchanger I've been struggling with my ice storage model for a long time, and I'v

2021-05-09 08:38:25 -0500 edited answer Control of Ice Storage model with Heat Exchanger

With great help from @szsz, I managed to make my model work, though it's not perfect. Here is the fixed IDF file. Pro

2021-05-09 08:36:08 -0500 answered a question Control of Ice Storage model with Heat Exchanger

With great help from @szsz, I managed to make my model work, though it's not perfect. Here is the fixed IDF file. Pro

2021-05-04 04:38:17 -0500 commented answer How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

@ericmartinpe Another thing that doesn't make sense is that reheat coil is almost always operating in summer. In order t

2021-05-04 03:01:16 -0500 commented answer How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

@ericmartinpe Thank you for fixing my idf file. However, the result is not what I expect. Your OA flow plots are from Se

2021-05-02 00:07:30 -0500 commented answer How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

Hi @ericmartinpe, thank you for your response. I followed these changes. OA flow is steady, but the total flow is also s

2021-04-27 02:15:32 -0500 received badge  Enthusiast
2021-04-26 00:37:04 -0500 edited question How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate? Any model is fine, but let me explain the current issue by us

2021-04-26 00:36:19 -0500 edited question How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate? Any model is fine, but let me explain the current issue by us

2021-04-25 23:24:47 -0500 edited question How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate? Any model is fine, but let me explain the problem using an Ex

2021-04-25 21:29:23 -0500 edited question How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate? Any model is fine, but let me explain the problem using an Ex

2021-04-25 21:19:18 -0500 edited question How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate?

How can HVACTemplate:Zone:VAV ensure Minimum OA Flow Rate? Any model is fine, but let me explain the problem using an Ex