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2019-06-14 11:00:16 -0500 edited answer add new actuators by changing the source code of EnergyPlus

To learn how to add a new actuator, search the code for the name of an existing actuator. For example, search for "AirTe

2019-06-14 10:59:36 -0500 edited answer add new actuators by changing the source code of EnergyPlus

To learn how to add a new actuator, search the code for the name of an existing actuator. For example, search for "AirTe

2019-06-13 17:19:05 -0500 answered a question add new actuators by changing the source code of EnergyPlus

Reluctantly repeating an answer from the helpdesk here, because this question was asked in both places...... To learn h

2019-06-13 17:12:52 -0500 commented question Fix the operative temperature of the zone

In EnergyPlus, the HVAC equipment (especially ideal loads) attempts to peg the setpoint. Deadbands in EnergyPlus refer t

2019-06-13 17:07:45 -0500 answered a question Positively pressurized ventilation system.

AirflowNetwork:ZoneControl:PressureController should work within the airflow network model, see example file AirflowNetw

2019-06-13 16:55:51 -0500 answered a question Variable speed fan powered terminal units

Repeating this answer here since this post was referenced here https://unmethours.com/question/38879/how-to-model-fan-po

2019-06-13 16:53:26 -0500 edited answer How to Model Fan Powered Boxes with VFDs?

This feature is not available in EnergyPlus yet (v9.1). I see you posted a new feature request, issue #7311. Hint: Votin

2019-06-13 16:52:51 -0500 answered a question How to Model Fan Powered Boxes with VFDs?

This feature is not available in EnergyPlus yet (v9.1). I see you posted a new feature request, issue #. Hint: Voting up

2019-06-13 16:35:12 -0500 answered a question What is the Connector List Name field in the AirLoopHVAC object for?

Connectors are used in dual duct air loops which are built using multiple branch objects. See example file DualDuctConst

2019-06-13 16:25:48 -0500 commented question Energyplus design heating load and airflow is zero

Normally, one would use a single schedule reference to cover all day types. Sure, you can do what you did above as long

2019-06-13 16:13:06 -0500 commented answer Batteries only charges to around 70 %

It's difficult to know what to suggest without seeing the full idf file. Please post a link here or send it to the helpd

2019-06-11 17:28:31 -0500 answered a question Batteries only charges to around 70 %

I would start by comparing inputs with the ShopWithPVandBattery example file, which does fully charge each day. Then I

2019-06-11 17:09:38 -0500 commented question Inconsistency in results from Winkelman and equivalent layer blinds models

Perhaps there is a good reason for the 2.5 cm limit in the IDD. How does this comparison look with 2.5 cm blinds?

2019-06-11 17:09:10 -0500 commented question Inconsistency in results from Winkelman and equivalent layer blinds models

Perhaps there is a good reason for the 2.5cm limit in the IDD. How does this comparison look with 2.5cm blinds?

2019-06-11 17:04:03 -0500 answered a question How replace autosized values with equivalent hardsize values for heating coils

Use the UFactorTimesAreaAndDesignWaterFlowRate method and autosize the UA and water flow rate. Then use the autosized va

2019-05-29 15:37:19 -0500 commented answer Turn off outside air for air loop during unoccupied period

The OA controller is not sensitive to nightcycle operation vs regular operation. If any of the minimum OA criteria are n

2019-04-19 11:06:51 -0500 commented answer When do you actually need a bypass pipe?

I would be sure to test that by creating a model you expect to fail.

2019-04-19 11:02:58 -0500 commented question Too many figures in a Shading Overlap

28x16 is nowhere near 15000000. I should have asked how many total surfaces are in the model. If you want to share the i

2019-04-19 10:56:38 -0500 commented answer When do you actually need a bypass pipe?

I don't understand the question here. Most (maybe all?) plant components will allow flow to pass through when they are o

2019-04-19 10:45:49 -0500 commented answer DOAS modeling with varying/scheduled OA cfm

No. If you configure the DOAS as a half-loop with no outdoor air system, then you do not need a Controller:OutdoorAir ob

2019-04-19 10:32:32 -0500 commented answer How to model an off-grid building?

If you would like to request new options for DemandManager, please create a new issue and add the label "NewFeatureReque

2019-04-19 09:37:59 -0500 commented answer Where user specified value disagrees with autosizing?

New issue posted #7276

2019-03-05 17:13:52 -0500 commented question Too many figures in a Shading Overlap

How many total shading surfaces are there in this model?

2019-03-05 17:07:39 -0500 answered a question EnergyPlus: Can Refrigeration:AirChiller be connected to Refrigeration:SecondarySystem through a Glycol loop?

It should be possible to connect Refrigeration:AirChiller to a secondary system. Reference the Refrigeration:AirChiller

2019-03-05 16:58:28 -0500 commented answer When do you actually need a bypass pipe?

And note that the ice storage units have a built-in bypass to regulate how much flow goes through the ice coils.

2019-03-05 16:55:40 -0500 answered a question When do you actually need a bypass pipe?

A bypass pipe is not required as long at the pump flow is variable or the parallel components can take all of the pump o

2019-03-05 16:52:03 -0500 answered a question DOAS modeling with varying/scheduled OA cfm

The current best practice for this is: Use AirTerminal:SingleDuct:ConstantVolume:NoReheat which can reference a Design

2019-03-05 16:31:58 -0500 answered a question Frame's area too large

In EnergyPlus, the area of a window (fenestration) surface is the glazed area inside the frame. The frame is added outsi

2019-03-05 16:29:06 -0500 answered a question How to model an off-grid building?

I am not completely sure this can be done. All electric demands must be met. If the PV plus storage cannot meet the curr

2019-03-05 16:10:21 -0500 answered a question New date formatting in "RUNPERIOD" section of idf file? fileupdate does not deal with this

The file conversion probably did not complete - check the version number in the final idf. It's probably not v9.0. The

2019-03-05 16:07:25 -0500 edited answer IDF Version Updater failing to convert

There is a known problem with the v9.0.1 transition programs (for transitions from v8.9 or older). See #7010 for a worka

2019-03-05 16:06:42 -0500 answered a question IDF Version Updater failing to convert

There is a known problem with the v9.0.1 transition programs (for transitions from v8.9 or older). See #7010 for a worka

2019-03-05 16:02:05 -0500 commented answer Issues with multiple FunctionalMockupUnitImport:To:Variables for same FMU.

@Thierry Nouidui There was a bug in the v9.0-9.1 transition packaged in the v9.1 idd freeze release. If you pull current

2019-03-05 15:58:15 -0500 commented answer Output average demand over a specific period with EnergyPlus?

To answer both questions, each table expects all of the columns to share a common key name, so there is no syntax for sp

2019-03-05 15:53:36 -0500 commented answer Zone Ideal Loads mismatch

Most likely yes. Report the System Node temperatures and humidities to see what's happening to help understand.

2019-02-08 14:04:57 -0500 commented answer Error while modeling radiant underfloor cooling system

ZoneHVAC:LowTemperatureRadiant:VariableFlow should work fine as cooling-only. Make sure that all of the fields related t

2019-02-07 17:48:32 -0500 commented answer Error while modeling radiant underfloor cooling system

It's still complaining about missing nodes and schedules. Will need to see your idf file in order to help further. Eithe

2019-02-07 17:38:52 -0500 answered a question Model using Zero Heating and Cooling

In the table output, the last subtable in the ABUPS reports is "Comfort and Setpoint Not Met Summary" which shows 1000s

2019-02-07 16:43:07 -0500 commented question CENTRAL HEAT PUMP SYSTEM INPUT

Is this what you mean by an air cooled chiller-heater? https://unmethours.com/question/1898/air-cooled-heat-pumps-to-pro

2019-02-07 16:34:18 -0500 answered a question Output average demand over a specific period with EnergyPlus?

If you wanted the monthly and annual averages during certain time windows, then you could use Output:Table:Monthly with

2019-02-04 15:44:22 -0500 commented answer How to model condensing gas-fired DHW tank in EnergyPlus?

@mldichter Yes, no change to this. @Julien Marrec Seems it would be fairly straightforward to allow WaterHeater:Mixed to

2019-02-04 15:23:46 -0500 commented answer Error while modeling radiant underfloor cooling system

See EnvironmentalImpactFactors and FuelFactors.

2019-01-28 17:14:17 -0500 answered a question May you help me to understand following warnings, please?

Just guessing, but it appears that most of the HVAC objects in this file are not autosized and have values entered for f

2019-01-28 17:06:30 -0500 answered a question Humidistat setting in Eneryplus

HVACTemplate:Zone:IdealLoadsAirSystem tries to make things simple for you and it automatically creates a ZoneControl:Hum

2019-01-28 16:56:40 -0500 commented answer Error while modeling radiant underfloor cooling system

Because this is a radiant system, use output variables "Zone Radiant HVAC Heating Energy" and cooling.

2019-01-18 09:48:13 -0500 answered a question Why the building load is not constant even if the weather file/internal loads/thermostats are set constant?

Add output variables for Site Sky Temperature and all of the Surface Outside Face * variables (well, the key ones). That

2019-01-18 09:25:44 -0500 answered a question Is A/K or V/K same as %/C on Temperature Coefficient?

/K and /C are equivalent, but not %. Take the mfr %/C for Voc and multiply it by the value for Open Circuit Voltage [V]

2019-01-18 09:19:48 -0500 answered a question energyplus zip window

You mean the zip file that is available on the GitHub release page. That is not an installer. It's just an archival zip

2019-01-18 09:07:04 -0500 answered a question Design Builder AirCooled Chiller with CelDek Pad using AHU condensate.

The simplest approach would be to set the Chiller:Electric:EIR Condenser Type to EvaporativelyCooledand adjust the total

2019-01-18 08:50:08 -0500 commented question solar oriention effect on energyplus output

With ideal loads, you won't see any change in electricity, but you should see changes in District Cooling and District H