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EnergyPlus version transition

asked 2018-05-16 10:09:53 -0500

M 108014 gravatar image

updated 2018-05-17 07:35:13 -0500

Hi, I am trying to change the version of my Energyplus from V8.5 to 8.6. After changing the version I am facing the following problem. I am wondering if anyone can provide me some suggestions:



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answered 2018-05-16 10:34:53 -0500

updated 2018-05-16 14:18:05 -0500

From the error message, it looks like you've got an uninitialized EMS variable. You'll need to provide an initialization. Uninitialized variables were previously allowed, but that was changed for version 8.6. Here's the issue that was raised:

And the pull request that made the change is here:

That link is failing to load for me right now (the dreaded GitHub angry unicorn), but the change is listed in the changelog here. It's listed under "Defects Repaired".

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I appreciate you help. If I figured that out correctly, I need to add W-AHZONE (which is applied in the program section) to the sensor section? Do you have any suggestion about the

a) Meter Index Key Name c) Meter name

which I need to complete in the sensor section?

M 108014 gravatar imageM 108014 ( 2018-05-16 16:00:53 -0500 )edit

Based upon the naming, that looks like a BEopt EMS program, and in one of the files I have that variable is connected to a "Zone Mean Air Humidity Ratio" sensor in the zone where the duct is. Assuming this is a BEopt file, @shorowit would probably know for sure.

Jason DeGraw gravatar imageJason DeGraw ( 2018-05-16 16:20:45 -0500 )edit

@M 108014 If this is a file originally generated from BEopt, it might be easiest to grab the latest version of BEopt and see what the new objects it writes are.

shorowit gravatar imageshorowit ( 2018-05-16 16:56:08 -0500 )edit

Also, if this is a BEopt file, the variable I see in the file I have is AHZONE_W, not W_AHZONE. Is it possible that the name got changed in one place and not the other?

Jason DeGraw gravatar imageJason DeGraw ( 2018-05-16 16:57:54 -0500 )edit

I really appreciate all your helps. This file is created originally in BEopt and then the first E+ version that we used for this one was in the version 7 range. Then I changed the version to 8.5 and it worked well. However, when I am changing the version to 8.6, I am facing the aforementioned problem. @Jason DeGraw I also have AHZone_W in my idf. Is that correct to have both?

I checked the W_AHZone and it is only used in the following expression: Set LatentLeakageToAHZone = f_sup * AH_MFR * h_fg * (AH_Wout - W_AHZone)

M 108014 gravatar imageM 108014 ( 2018-05-16 18:54:02 -0500 )edit

answered 2018-05-16 21:04:09 -0500

M 108014 gravatar image

I changed the W_AHZone to AHZone_W and it worked. The simulation is successful. Thanks @shorowit and @Jason DeGraw. My final goal is to reach v8.9. The simulation is successful with the same approach till 8.8. Bu when I am trying to transit from 8.8 to 8.9, I am getting the following error message before warm up. Could you please also help me with that. I compared the idf of V8.8 and v8.9. Nothing unless the version is different!

C:\fakepath\New Warning.PNG

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The simulation encountered a fatal error and did not indicate the reason. The "node connection errors not checked" tells you that node connections were not tested yet. So there is no indication of the failure in these messages. The input file is needed in order to diagnose.

rraustad gravatar imagerraustad ( 2018-05-17 06:51:20 -0500 )edit

This sounds like something different to me, so please create a separate question.

Jason DeGraw gravatar imageJason DeGraw ( 2018-05-17 08:03:15 -0500 )edit

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Asked: 2018-05-16 10:09:53 -0500

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Last updated: May 16