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Is there a limit to the number of thermal zones?

asked 2015-07-27 09:51:20 -0600

kounelak1's avatar

updated 2015-07-27 19:37:15 -0600

I have to simulate a 7-floor building and after thermal zone no.22, or 23 the program does not let me create more zones. Why is this happening? I open the window to select "new thermal zone" but it closes automatically and selects "clear field". Can I fix it?

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@kounelak1 What program are you referring to? This site is used for all building simulation programs. Can you add the name of the program to the tag list?

Neal Kruis's avatar Neal Kruis  ( 2015-07-27 10:20:34 -0600 )edit

I'm using SketchUp OpenStudio

kounelak1's avatar kounelak1  ( 2015-07-27 12:00:04 -0600 )edit

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answered 2015-07-27 14:56:52 -0600

I recommend that you create the ThermalZone instances in the OpenStudio Application as shown here. You should not run into a limit in the App and if you do then please file an issue.

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If you do use the plugin try to use the space attributes tool to create an assign thermal zones to geometry instead of using the inspector. There is also a user script to add a thermal zone to spaces that don't already have a thermal zone assigned. That is fine to use.

David Goldwasser's avatar David Goldwasser  ( 2015-07-27 15:16:45 -0600 )edit

I'll use energy plus for the rest. I just have to simulate in SketchUp OpenStudio my building with the thermal zones, I won't use the OpenStudio application. Is there really a limit? Is there a way to fix it without using the application?

kounelak1's avatar kounelak1  ( 2015-07-27 15:18:24 -0600 )edit

I use the space attributes tool to create a thermal zone, and then I use the inspector to rename it. But now I have this problem. I'll try the user script! I hope it works! Thanks!

kounelak1's avatar kounelak1  ( 2015-07-27 15:42:59 -0600 )edit

The user script worked! But now, every space is a different zone, and I would like to have the same thermal zone in two differnet spaces. I tried to rename them, so that they are in the same zone, using the inspector, but it just renames the first for example "C" and the other one "C 1". Any ideas?

kounelak1's avatar kounelak1  ( 2015-07-27 18:22:43 -0600 )edit

answered 2015-07-29 15:19:48 -0600

Archmage's avatar

There is no limit on the number of thermal zones in EnergyPlus. Eventually the computer may not have enough memory to run a really really huge model, but the code does enforce a limit.

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answered 2020-08-11 16:42:33 -0600

updated 2020-08-11 22:19:47 -0600

I can confirm that OpenStudio 2.9.1 will not allow me to add more than 103 thermal zones.

Update: See comments below. It appears there is no limit.

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Did you hit this limit in the SketchUp Plug-in or the App? If it was in the plug-in, my guess is that the plug-in crashed for some other reason (like an undo action). As far as I know there should be no hard limit on the number of spaces or zones.

macumber's avatar macumber  ( 2020-08-11 21:05:36 -0600 )edit

Thank you Dan. I was using the x2 command in the App (on the thermal zones tab). It stopped working. I "revert to saved" and it still did not work. Now that I have closed it out and reopened the OSM file, and see that it will let me use the + command. I was able to successfully add more zones. So, it appears there is no limit. Perhaps there is a bug with the x2 command or there was a RAM problem (I was running a bunch of other stuff at the same time).

Ski90Moo's avatar Ski90Moo  ( 2020-08-11 22:18:51 -0600 )edit

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Asked: 2015-07-27 09:51:20 -0600

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Last updated: Aug 11 '20