Pollination Local Running Error

Hi, I encountered the following errors when trying to run pollination locally. Any idea how to fix it? Thanks!

2022-08-08 16:37:56 ERROR: [pid 16160] Worker Worker(salt=298794700, workers=6, host=ME1M014, username=XDu, pid=18920) failed RunSimulation(_input_params={“additional_idf”: null, “ddy”: “USA_ME_Waterville.AWOS.726073_TMY3.ddy”, “epw”: “USA_ME_Waterville.AWOS.726073_TMY3.epw”, “measures”: null, “model”: “qdrplkxb.sxd.hbjson”, “params_folder”: “__params”, “sim_par”: “hqsvxjz3.zbf.hbjson”, “simulation_folder”: “C:/Users/xdu/simulation/Unnamed/Unnamed”, “units”: “si”, “viz_variables”: “”}, additional_string=)
Traceback (most recent call last):
File “c:\program files\ladybug_tools\python\lib\site-packages\luigi\worker.py”, line 191, in run
new_deps = self._run_get_new_deps()
File “c:\program files\ladybug_tools\python\lib\site-packages\luigi\worker.py”, line 133, in run_get_new_deps
task_gen = self.task.run()
File "c:\program files\ladybug_tools\python\lib\site-packages\queenbee_local_init
.py", line 273, in run
raise ValueError(err_msg)

Failed task: RunSimulation.
Run the command with --debug key to debug the workflow.

Hi @sunnydu, there is a log file with more details that you should see at the end of the run report. Can you share that file with us? Something went wrong in the main step to run the energy simulation.

Hi @mostapha I found it’s caused by some HVAC problems - specifically, UA sizing failed in some systems. Since all the systems are autosized, any suggestion to correct this error? (I tried to upload the ERR file but it says the file type is not supported).

** Severe ** Autosizing of heating coil UA failed for Coil:Heating:Water “ROOM_2DB19777 PSZ-AC WATER HTG COIL”
** ~~~ ** Bad starting values for UA
** ~~~ ** Lower UA estimate = 2.941756 W/m2-K (1% of Design Coil Load)
** ~~~ ** Upper UA estimate = 2941.756170 W/m2-K (100% of Design Coil Load)
** ~~~ ** AirloopHVAC “IECC2021 SYS9 PRHP - ROOM_2DB19777 PSZ-AC” coil sizing conditions (may be different than Sizing inputs):
** ~~~ ** Coil inlet air temperature = -3.093 C
** ~~~ ** Coil inlet air humidity ratio = 3.497E-003 kgWater/kgDryAir
** ~~~ ** Coil inlet air mass flow rate = 5.513909E-002 kg/s
** ~~~ ** Design Coil Capacity = 0.000 W
** ~~~ ** Design Coil Load = 2941.756 W
** ~~~ ** Inadequate water side capacity: in Plant Sizing for this hot water loop
** ~~~ ** increase design loop exit temperature and/or decrease design loop delta T
** ~~~ ** Plant Sizing object = HOT WATER LOOP
** ~~~ ** Plant design loop exit temperature = 48.888 C
** ~~~ ** Plant design loop delta T = 11.111 C
** Severe ** Developer Error: sizing of U-Factor Times Area Value [W/K] failed.
** ~~~ ** Occurs in Coil:Heating:Water ROOM_2DB19777 PSZ-AC WATER HTG COIL
** Fatal ** Preceding water coil sizing errors cause program termination

Hi @sunnydu, Thanks. I think this part includes suggestions on fixing the issue. :point_down:

Maybe @mingbo or @chriswmackey can provide better suggestions.

@mostapha thanks - however, I don’t seem to find options to change HVAC sizing in the Rhino plugin.

Hey @sunnydu ,

Can you upload a minimal sample file that is needed to recreate the issue? I imagine that you’ll get an error like this if the thermostat setpoints are at an extreme value or there are some unconventional design day conditions but, if this is happening under relatively standard conditions, then this might be an issue that the E+ or OpenStudio Standards developers could investigate and improve.

There are also a few different workarounds for this. The quickest and most manual one is to save the model to OSM, open it in the OpenStudio Application, and specify hard sizes for equipment there. Other possible workflows include IronBug, OpenStudio Measures, or using the OpenStudio SDK inside a GHPython component.

But let’s see if we can figure out why this situation is happening in the first place before trying these workarounds.

Hi @sunnydu ,

Sorry for the late response. I see that you sent me a file via email but it has a few validation errors:

I recommend fixing these before trying to simulate the model.

You also have some overlapping Room volumes like this one, which are not currently caught by the validation command but I can’t imagine that they are intentional:

So the first step is to fix these issues. If the error still persists after that, let us know and I’ll investigate further.

Actually, @sunnydu , I was able to create a minimal sample file with the error and I can see that this simulation error will still be around even after you fix all of the issues that I pointed out with your model above.

The root cause of the problem is that the “Data” room in your model had zero need for heating on the winter design day (it is deep in the core of the building after all). It seems that the “Packaged Single-Zone system with a central ASHP” (from the OpenStudio Standards package) isn’t built to handle this case of no heating demand and so the simulation fails.

I imagine that the developers of the OpenStudio Standards Gem might consider this a bug and I can let them know about it.

The easiest way to fix the issue right now is to change the HVAC system assigned to the “Data” Room to be a PSZ-AC (without any heating) and you should then have a successful simulation. This is probably closer to what would happen in the real building since I imagine you would not put a heating coil in a room that didn’t have any need for it.

I reported the issue to NREL:

FYI, another good option for this case is to use the PSZ-HP template since it’s still a heat pump system but it’s directly integrated into the air handling unit, which probably makes it cheaper and more efficient in most cases.

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