URGENT the ApacheSim will not run because of MacroFlo link..

[kana34]

Hi

Im trying to run ApacheSim when it says:

Error in MacroFlo. Maximum pressure exceeded in a room (..). Likely cause: air being supplied/extracted when openings are closed.

What to do? The system is very simple, no HVAC, just heating. I will be very grateful for any help.

A.

[kana34]

I have been trying to add windows, change everything, doesn't want to work.. it is a very urgent matter. Can it be a problem with weather file? Im using the epw generator and pressure is in Pa (is it correct?) There were already problems with radiation when I was using the spreadsheet to create my weather file..

[PCully]

Hi,

I haven't seen this error before when an ApacheHVAC system isn't in use, the room that is being reported may not be on the ApacheHVAC system but if there is an imbalance elsewhere in the model due to the forced ventilation then that may manifest and report as an error in another of the rooms that is only naturally ventilated using MacroFlo. One easy way to isolate the true room where the imbalance occurs is to edit MacroFlo Opening profiles so that all openings are closed (with no infiltration either) and then run the simulation again, this time you should get the true problem.

If you are definitely not running with the ApacheHVAC link on then you should just begin to troubleshoot and review the model as is. ideas that come to mind (I don't really know what else could cause this) would be

- double check you have no external holes
- check the quality of your model geometry (in ModelIT Settings menu >> Model... tick on Intersections, Zones and Surfaces and click Check to get a report)
- review all opening types and any formulae profiles in use to ensure they are valid

You could also run with another simulation weather file, since you mentioned it, if you choose a similar location then systems and openings should behave mostly the same. Perhaps your custom file does have errors, it's hard to say though. Opening the weather file in Vista would potentially flag up problems and again you could plot the suspect variables against a valid fwt file to ensure they are within a reasonable range (look at peaks, averages etc)

Phil

[kana34]

Hi

Thank you so much for that. I have checked with .fwt- it works fine. But apparently none of epw files does the job. Is there any other epw creator that I could use? The only variable I REALLY care about is the temperature. I was trying to use EU spreadsheet- after exporting it Apache says the weather file is incomplete.

Thank you

[kana34]

I have actually run it on epw file that I've exported from the creator spreadsheet without changing anything- to check if it is not my fault that I am editing it in a wrong way. But it doesn't work anyway.. changing Pa to hPa (as there is a discrepancy between UK and EU editors) is not helping either. The files work fine until MacroFlo is employed.

[PCully]

I'll see if anyone in here has created an EPW file (I've never done it myself) and then test the sim with MacroFlo to see if it works or not. If not I can ask one of our developers to troubleshoot for me and we can find out if there is a problem here.

I shall post back any results but I'd still say try comparing your custom files to some of the fwt files that do run to see if you can spot the discrepancy

Phil

[Ecorce]

Hi,

I have the same problem as the one described in this post: "error in Macroflo. Maximum pressure exceeded in zone..." The model has no external holes, no intersections.
It works well with the .fwt file but doesn't work with the epw file created with the weather file creator.

Could you please tell me how this problem was solved ?

Thanks a lot !


Danielle