Knowledge Base

COMFEN 5
(5.0.05 -- January 1, 2013)

Last update:09/11/13 11:40 AM

Download COMFEN 

Release Notes
(includes a list of changes to the program by version)

Send feedback via email to COMFENHelp@lbl.gov. Also as bugs and comments are submitted by testers, they will be posted on this Knowledge Base, so check here for the latest information about the program.

CONTENTS

INSTALLATION   KNOWN ISSUES
 
 
 
 
 
   
   
   
TIPS    
   
   
  BUG FIXES
 
 
   
   
   
   
   
   
   

 


INSTALLATION:

Installation Issues -- Administrator

In order to install the program with the Microsoft NT (4.0), 2000, and XP, you must be Administrator on your machine. To check if you are Administrator, do the following:

Go to Start,  Settings, Control Panel, Users and Passwords. 
Find the current username (yours) and look in the group column. It should say: Administrators
If the current username does NOT say Administrators, contact your IP department to become Administrator, or to have someone with Administrator privileges install the program on the machine.
Microsoft Windows 7: if you are installing COMFEN on a computer with MS Windows 7, you may need to right click on the installation program (in Explorer) and say "Run as Administrator" in order to install the program.

Microsoft.NET must be on your computer

In order for COMFEN3 to work, you must have Microsoft.NET on your computer. To determine whether you have Microsoft.NET, go to the operating system directory (WINDOWS for Microsoft XP), and see if there is a Microsoft.NET directory there:

Here is a link to the Microsoft.NET website:

http://www.microsoft.com/NET/

Click on the Download button at the top to download an EXE which you can then run to have .NET installed on your computer.

Installation Directories by Operating System 
The following structure shows where the program is installed depending on your computer's operating system:

Microsoft XP:

All program files are initially installed into:

                    c:\Program Files\LBNL\COMFEN4_1.

User files (or other files that may change) are copied (the first time you run the program) into:

                    c:\Documents and Settings\<username>\Application Data\LBNL\COMFEN4_1

This is where you would look for the project database (under the db subdirectory) and EnergyPlus results files (under the results subdirectory

Microsoft Windows 7:

All program files are initially installed into:

c:\Program Files (x86)\LBNL\COMFEN4_1

User files (or other files that may change) are copied (the first time you run the program) into:

c:\Users\<username>\AppData\LBNL\COMFEN4_1

This is where you would look for the project database (under the db subdirectory) and EnergyPlus results files (under the results subdirectory

Minimum computer requirements:

Pentium class or better.
At least 32 MB of random access memory (RAM). For optimal operation, 64 MB or more of RAM is preferrable.
Microsoft Windows 98TM, Windows 2000TM, Windows XPTM, Windows METM, or Windows NTTM
(The program WILL NOT run with Windows 3.1TM,  Windows NT 3.51TM or Windows 95TM). 
Hard disk drive with at least 150 MB of available disk space
Printer supported by Microsoft Windows (serial, parallel, or shared over a network).
Optics5 Note: The latest version of Optics5 that is available for download IS compatible with WINDOW 5.2

 

Reporting Computer System Info to LBNL for Troubleshooting

 

 

Microsoft.NET must be on your computer

In order for COMFEN3 to work, you must have Microsoft.NET on your computer. To determine whether you have Microsoft.NET, go to the operating system directory (WINDOWS for Microsoft XP), and see if there is a Microsoft.NET directory there:

Here is a link to the Microsoft.NET website:

http://www.microsoft.com/NET/

Click on the Download button at the top to download an EXE which you can then run to have .NET installed on your computer.

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TIPS

Building Types

The following building types are available: Mid-Rise Residential, Hotel, Retail, School (Classroom). The change to the program for these building types is to change the operating schedules. The Building Type is set in the by going to the Project / Properties menu. Click here to download a PDF file that contains a description of the schedules for the different Building Types

CSV Input for Creating Scenarios

It is now possible to import a CSV file to create a scenario. Click here to download a PDF file that explains how to use this feature. With the addition of the Glazed Wall Assembly, there are now two different formats for the CSV input files:

Make sure that you set the units in COMFEN (SI or IP) to the same unit system used in the CSV data. If you created the data assuming SI units, and then import it into COMFEN with the program set to IP units, the program will think that the values in the CSV file are in IP units and the input will be very wrong !!!

File Locations
COMFEN has a somewhat complicated system for where files are located. Here are two links for more information:

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KNOWN ISSUES

Between Blind Slat Width Greater than Glazing System Gap

Energy Plus crashes when if the slat width of a between-glass venetian blind is greater than the width of the gap in the glazing system. When defining a venetian blind, make sure to make the slat width less than the glazing system width.

Site To Source Multiplier -- changing it does not invalidate results

Changing the Site to Source multiplier (in COMFEN\Preferences) does not invalidate the results, so make sure to recalculate the Scenarios if you change this value.

Natural Ventilation -- heating load increases

You may notice an increase in the heating load when running a scenario with natural ventilation. We are still investigating the exact cause of this in the Energy Plus simulation engine, but what we are seeing when we look at the time step reports (15 minute increments or less) is that every time the fans come on the heat also comes on. The program then checks the zone temperature, determines whether the heat really needs to be on, and if it doesn't, turns it off. So in the periods where heating is not actually needed, it is not on for very long (15 minutes or less) but over the entire year, that adds up in terms of a heating load. We are working with the Energy Plus development team to understand the cause of this behavior in the program, and will update the COMFEN Energy Plus model when a solution is found.

Climate Data Does Not Display

If the Climate Data is not displaying in the Climate tab, it is because the current installation of COMFEN 5 does not include a file update needed for this display. Click here to download a zip file containing the latest for_cwf_generation.idf file. Put it in the following directory (overwriting the existing file)

Windows 7 / Vista Operating Systems:

C:\Program Files (x86)\LBNL\COMFEN5\EnergyPlus\lib

XP Operating System:

C:\Program Files (x86)\LBNL\COMFEN5\EnergyPlus\lib

Problems with Australian Weather Files

The weather files for Australia (EPW and DDY) that are in the COMFEN installation do not run. In order to get weather files that allow an EnergyPlus simulation, go to the Energy Plus Weather Data website and download the files. They then need to be copied into the C:\Program Files (x86)\LBNL\COMFEN5\Weather directory.

BUG FIXES

Project North No Longer Restricted to 30 degrees

Project North (found in File / Project Properties) is used to offset the cardinal orientation of a facade by the degree value entered. In previous versions, the rotation is restricted to + 30 degrees-- this has been fixed, so that now the Project North values can be values from 180 degrees to -180 degrees (inclusive).

Current Energy Plus Weather Files Work with COMFEN 5.0

In COMFEN 4.0, the current weather files for Energy Plus would not run because it was running an older version of Energy Plus. COMFEN 5.0 has an updated version of Energy Plus, and will now run with the current weather data available from the Energy Plus Weather Data website:http://apps1.eere.energy.gov/buildings/energyplus/weatherdata_about.cfm