Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

MJWitte's profile - activity

2019-01-08 17:25:31 -0600 commented answer Glycol Cooling coil with Temperature below zero in E+. How to model?

In theory, yes, can be used with refrigerant or brine. See example file SupermarketSecondary.idf to see how secondary sy

2019-01-08 17:18:31 -0600 answered a question EMS:ProgramCallingManager with 4 plant loops without overwriting?

If you have unique variable names for the actuators, then there should be no overlap. Check the detailed line-by-line ou

2019-01-08 17:16:27 -0600 commented answer Control LowTemperatureRadiant using indoor and outdoor temperature with EMS?

Oh, I see. You could use a unique availability schedule for each ZoneHVAC:LowTemperatureRadiant:ConstantFlow and then ac

2019-01-07 15:02:34 -0600 answered a question Error while modeling radiant underfloor cooling system

Based on the error messages, it appears that the radiant system has not been connected to a working plant loop. If that'

2019-01-07 14:54:41 -0600 answered a question OpenStudio Simulation Went Wrong. Help, Please!

A quick review of the HVAC system shows a single duct VAV system with reheat with a fixed supply temperature year-round

2019-01-07 14:35:29 -0600 edited answer Controlling the zone thermostat with thermal comfort models

In the EnergyPlusVn-m-0\ExamplesFiles folder, there are two files that index all of the example files. ExampleFiles.html

2019-01-07 14:34:58 -0600 answered a question Controlling the zone thermostat with thermal comfort models

In the EnergyPlusVn-0-0\ExamplesFiles folder, there are two files that index all of the example files. ExampleFiles.html

2019-01-07 14:26:57 -0600 commented answer Control LowTemperatureRadiant using indoor and outdoor temperature with EMS?

What is "TABS"? I am not sure I understand the question, but here is a suggestion: SET BoilerTABSday=0, IF (Outd

2019-01-07 14:15:48 -0600 commented answer Glycol Cooling coil with Temperature below zero in E+. How to model?

See example file RefrigeratedWarehouse.idf to see how Refrigeration:AirChiller is applied.

2018-12-31 09:56:30 -0600 commented question Command line interface (CLI) and EPMacro

But that would be the same on Windows - file extension.

2018-12-31 09:55:45 -0600 commented question Command line interface (CLI) and EPMacro

Not sure what else it could be, the CLI code is the same for Windows and Linux unless you happen to be using Win32 exe.

2018-12-31 09:35:36 -0600 answered a question Equipment not sizing

In the chiller objects, the "Reference Chilled Water Flow Rate" is not autosized. This can be seen in the "Component Siz

2018-12-31 09:11:20 -0600 answered a question Is there a way to model "proper" control of a UFAD system in EnergyPlus?

You are correct that the RoomAirSettings:* objects define the UFAD characteristics for the thermal stratification model.

2018-12-31 08:53:47 -0600 commented question Earth Tube Zone Sensible Cooling/heating Energy is unusual!

Please post a link here to the idf files, or send them to the helpdesk at energyplus-support@gard.com (include a link to

2018-12-31 08:49:41 -0600 answered a question Control LowTemperatureRadiant using indoor and outdoor temperature with EMS?

Disabling a boiler or chiller will not shut down the entire plant loop. Add an AvailabilityManager:Scheduled for each pl

2018-12-31 08:43:47 -0600 commented question Command line interface (CLI) and EPMacro

For both Windows and Linux, the CLI links the idf path to the current-working-directory/in.imf. From the error message,

2018-12-31 08:43:12 -0600 commented question Command line interface (CLI) and EPMacro

For both Windows and Linux, the CLI links the idf path to the current-working-directory/in.imf. From the error message,

2018-12-31 08:42:32 -0600 commented question Command line interface (CLI) and EPMacro

For both Windows and Linux, the CLI links the idf path to the <current working="" directory=""> /in.imf. From the

2018-12-31 08:42:05 -0600 commented question Command line interface (CLI) and EPMacro

For both Windows and Linux, the CLI links the idf path to the <current working="" directory="">/in.imf. From the e

2018-12-31 08:41:45 -0600 commented question Command line interface (CLI) and EPMacro

For both Windows and Linux, the CLI links the idf path to the <current working="" directory="">\in.imf. From the e

2018-12-31 08:17:51 -0600 commented answer Ground Slab/basement Modelling-water reservoirs and wells

Given that the thermal mass varies as water enters and leave the cistern, and these flows move energy in and out of the

2018-12-26 17:12:06 -0600 answered a question WindowEquivalentLayer model - Glass Visible Transmittance

It's not clear in the documentation, but WindowEquivalentLayer does not work with daylighting. The reported VT of zero i

2018-12-26 16:56:33 -0600 answered a question Condenser Loop - Pump:VariableSpeed always running

Looking at the hourly output for the chiller and the pumps, the condenser pump only runs when the chiller operates, whic

2018-12-26 15:08:16 -0600 answered a question Heating airflow sizing for AirTerminal:SingleDuct:VAV:Reheat

From the Input Output Reference for AirTerminal:SingleDuct:VAV:Reheat for "Minimum Air Flow Fraction Schedule Name":

2018-12-26 14:48:52 -0600 commented answer Ground Slab/basement Modelling-water reservoirs and wells

That's a starting point, but the cistern has side walls which add another dimension to the heat transfer, and possibly m

2018-12-20 14:31:00 -0600 commented answer EP9.0.1 crashes when external shading is imported from file

My understanding of the current implementation is that it expects 8760 hourly values. No.

2018-12-20 14:27:57 -0600 answered a question Zone ideal load zone latent cooling/Heating rate

The zone humidity ratio is the result of the ideal loads flow (as the specified constant humidity ratio), the latent loa

2018-12-20 14:23:55 -0600 commented answer Ashrae sizing: Zone Sensible Cooling and ZoneHVAC:IdealLoadsAirSystem

Ok, so you're referring to the "Component Sizing Summary" report. Starting with that base file, a couple of things need

2018-12-20 12:05:28 -0600 commented answer Sizing-day run period failed to achieve the setpoint

Make sure that every schedule is appropriate for the WinterDesignDay and SummerDesignDay day types. Common design practi

2018-12-14 16:34:56 -0600 commented question Zone ideal load zone latent cooling/Heating rate

What else is going on in the zone? Infiltration? People? Is the ideal loads system adding outdoor air?

2018-12-14 16:28:20 -0600 answered a question Sizing-day run period failed to achieve the setpoint

You are correct that the sizing period simulations are the basis for the sizing calculations. Without a description of t

2018-12-14 16:23:31 -0600 commented question Mismatch of Air heat balance and inside heat balance.

Answered this over in the original post

2018-12-14 16:15:41 -0600 commented answer How does the Energyplus calculate the ideal loads?

See Answer Part 2 above.

2018-12-14 16:15:29 -0600 edited answer How does the Energyplus calculate the ideal loads?

That equation is a correct representation of the zone heat balance. All of the components of the heat balance are availa

2018-12-14 13:48:11 -0600 commented answer Ashrae sizing: Zone Sensible Cooling and ZoneHVAC:IdealLoadsAirSystem

You refer to an html table for "ZoneHVAC:IdealLoadAirSystem". I don't know what table that is. Please provide a link to

2018-12-14 13:40:17 -0600 commented question IDF parsing error for WindowShadingControl in v9.0

Then it sounds like this is an OpenStudio question. It may be that OS is taking a shortcut and writing a single WindowSh

2018-12-14 13:32:49 -0600 commented answer How does the Energyplus calculate the ideal loads?

The link is prompting for a login

2018-12-14 13:30:09 -0600 commented answer Glycol Cooling coil with Temperature below zero in E+. How to model?

And be sure to add output variables for all of the node conditions entering and leaving the coil so you can verify if en

2018-12-14 13:29:11 -0600 commented answer Glycol Cooling coil with Temperature below zero in E+. How to model?

A quick check of the coil source code does not reveal any error messages related to freezing temperatures, so it may wor

2018-12-11 15:45:24 -0600 answered a question IDF parsing error for WindowShadingControl in v9.0

IDF Editor works off the object definitions in the EnergyPlus IDD file, energy+.idd located in the root EnergyPlus insta

2018-12-11 15:20:15 -0600 answered a question Glycol Cooling coil with Temperature below zero in E+. How to model?

EnergyPlus supports glycol plant loops, and the water-side of Coil:Cooling:Water is able to handle temperatures below fr

2018-12-11 15:14:05 -0600 edited question Glycol Cooling coil with Temperature below zero in E+. How to model?

Glicol Cooling coil with Temperature below zero in E+. How to model? I have to model a Glicol Cooling system where the G

2018-12-11 15:11:47 -0600 commented question Mismatch of Air heat balance and inside heat balance.

When posting a followup question, please include a link referencing the original post. Again, it's impossible to answer

2018-12-11 15:09:03 -0600 commented answer How does the Energyplus calculate the ideal loads?

It's impossible to answer this without seeing the input files. Please post a link here or send them to the helpdesk at e

2018-12-11 15:04:57 -0600 commented answer Sum up Variables Over SystemTimeStep (EMS_E+)

The problem here is that the EMS calling point is EndOfZoneTimestepBeforeZoneReporting which happens only once per zone

2018-12-07 08:40:38 -0600 commented question How to simulate a biodigester with E+

Theoretically, one should be able to add a large amount of thermal mass to a zone. What kind of errors did you get?

2018-12-06 17:50:19 -0600 answered a question Monthly cooling coil sensible outputs.

This is a known issue in v8.9 and v9.0.1 (and maybe earlier). The workaround is to add Output:Variable objects for the v

2018-12-06 17:46:53 -0600 commented question How to simulate a biodigester with E+

Theoretically, once should be able to add a large amount of thermal mass to a zone. What kind of errors did you get?

2018-12-06 17:32:21 -0600 answered a question How does the Energyplus calculate the ideal loads?

That equation is a correct representation of the zone heat balance. All of the components of the heat balance are availa

2018-12-04 15:00:33 -0600 answered a question EP9.0.1 crashes when external shading is imported from file

Question was also posted to the helpdesk, ticket 13119, repeating answer here for everyone else. Delete the first line