search

kbenne / cbecc

Automatically exported from code.google.com/p/cbecc
0 stars 0 forks source link

CBECC-Com Issue - HVAC #908

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago 
For the attached model, there are no errors at the beginning, while after a few 
mins running, it shows the below window saying there is an error encountered 
simulating standard sizing model. I have no idea what does this error mean. I 
have the model attached. It is really urgent, really appreciate if you could 
take a look at it at your earliest convenience.

Version = 2013_3_653

Category = HVAC

Original issue reported on code.google.com by f.le...@gmail.com on 21 Jan 2015 at 10:16

GoogleCodeExporter commented 9 years ago 
There are 2 issues that I see in your Simplified Geometry model “Hilton 
II_20150116.cibd”.

1. You will need to add interior walls to some of your spaces.  For interior 
walls between two adjacent spaces you only need to model the interior wall once 
in one of the spaces (not in both spaces), and then assign the name of the 
adjacent space in the interior wall object.   Some of your spaces could have 
more than one interior wall based on the number of exterior walls and shape of 
the space.

2. If a floor is touching the ground then you should right click on your space, 
go to create, and select “Underground Floor”.  Each space in your model is 
showing an “Interior Floor”.  Interior Floors would only be used between 
floors so you can build the surface in one space then reference the adjacent 
space below in the Interior Floor objects. 

Noah

Original comment by ncz...@archenergy.com on 22 Jan 2015 at 7:37

GoogleCodeExporter commented 9 years ago 
The error you were was due to extreme temperatures for certain building 
surfaces.  These were due to the very light weight of the constructions 
assigned to the surfaces of the spaces, Rm 113 in particular.  In the attached, 
I added two layers of gypsum board to your floor and roof constructions to 
increase their thermal mass, and the simulation runs through to completion, 
although it is still failing due to unmet load hour limits being exceeded.  You 
will need to increase system capacities and check control settings to correct 
the unmet load hours.

Original comment by rhedr...@archenergy.com on 22 Jan 2015 at 10:19

GoogleCodeExporter commented 9 years ago 
In further testing of this model, it was found that all zones had cooling UMLHs 
due to the chiller not being run to meet the load.  It was found this was 
caused by specifying a 'VariableSpeed' pump as the child of the chiller, i.e. a 
variable speed branch pump on the primary side of the pri/sec loop.  

Changing the pump to "ConstantSpeed" resolves the issue. 

To mitigate this in future releases, a CHECKSIM rule has been added to provide 
uses a warning of this configuration, and automatically change the proposed 
pump control to 'ConstantSpeed' for the annual simulation.

Original comment by da...@360-analytics.com on 26 Jan 2015 at 9:25

GoogleCodeExporter commented 9 years ago 
Rules to reflect comment #3 committed @ r2984

Original comment by da...@360-analytics.com on 26 Jan 2015 at 10:20