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HI, I am working on a LEED energy model for a data center. The design case model ran through fine but my baseline model crashes with the following error:

 ** Severe  ** Temperature (high) out of bounds (202.78] for zone="FLR3_WHITESPACE_A4.03.WS", for surface="6892E3"
   **   ~~~   **  During Warmup, Environment=AMSTERDAM ANN HTG 99.6% CONDNS DB HVAC Sizing Pass 1, at Simulation time=01/21 15:30 - 15:40
   ** Severe  ** Temperature (low) out of bounds [-101.84] for zone="FLR3_WHITESPACE_A4.03.WS", for surface="DAFECC"
   **   ~~~   **  During Warmup, Environment=AMSTERDAM ANN HTG 99.6% CONDNS DB HVAC Sizing Pass 1, at Simulation time=01/21 15:30 - 15:40
   ** Severe  ** Temperature (low) out of bounds [-111.87] for zone="FLR3_WHITESPACE_A4.03.WS", for surface="6892E3"
   **   ~~~   **  During Warmup, Environment=AMSTERDAM ANN HTG 99.6% CONDNS DB HVAC Sizing Pass 1, at Simulation time=01/21 15:30 - 15:40
   ** Severe  ** Temperature (high) out of bounds (210.03] for zone="FLR4_WHITESPACE_A4.04.WS", for surface="B02EB9"
   **   ~~~   **  During Warmup, Environment=AMSTERDAM ANN HTG 99.6% CONDNS DB HVAC Sizing Pass 1, at Simulation time=01/21 15:50 - 16:00
   **   ~~~   ** Zone="FLR4_WHITESPACE_A4.04.WS", Diagnostic Details:
   **   ~~~   ** ...Internal Heat Gain [2114.971] W/m2
   **   ~~~   ** ...Infiltration/Ventilation [0.224] m3/s
   **   ~~~   ** ...Mixing/Cross Mixing [0.000] m3/s
   **   ~~~   ** ...Zone is part of HVAC controlled system.

The IT and electrical rooms have very high internal loads as it is a datacenter. These spaces are conditioned by system 4 - PTHP with single speed DX cooling, single speed DX Heating coils and constant flow fan. Based on my sizing calculations, the rated air flow per watt for the zones is 0.000075 m³/s per watt. According to the idd file, I see that this value should be between 0.00004027 m3/s and .00006041 m3/s per watt of rated total cooling capacity. Here is the error that I get:

   ** Severe  ** Sizing: Coil:Cooling:DX:SingleSpeed "FLR10_TECHSPACE_A4.10.11_PTHP-CCDX": Rated air volume flow rate per watt of rated total cooling capacity is out of range.
   **   ~~~   ** Min Rated Vol Flow Per Watt=[4.027E-005], Rated Vol Flow Per Watt=[7.500E-005], Max Rated Vol Flow Per Watt=[6.041E-005]. See Input Output Reference Manual for valid range.
   ************* SizeDXCoil: Potential issue with equipment sizing for Coil:Heating:DX:SingleSpeed FLR10_TECHSPACE_A4.10.11_PTHP-HCDX
   **   ~~~   ** User-Specified Rated Air Flow Rate [m3/s] = 7.12000
   **   ~~~   ** differs from Design Size Rated Air Flow Rate [m3/s] = 13.25438
   **   ~~~   ** This may, or may not, indicate mismatched component sizes.
   **   ~~~   ** Verify that the value entered is intended and is consistent with other components.

Is there a work around to get this Coil:Cooling:DX:SIngleSpeed component used with ZoneHVAC:PackagedTerminalHeatPump to work?

Thank you, Raghu

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Hi, I am working with OS v 1.7.0. I created my complete model and realized that some of my thermal zones did not need thermostats. I could delete the thermostat schedules using the OpenStudio GUI but my model was crashing as I could not delete the OS:ThermostatSetpoint:DualSetpoint objects that were created. Is there a way that I can delete these objects through the GUI? I tried deleting these objects after opening the OSM file in a text editor but read in the below post that it may not be a great idea.

https://unmethours.com/question/4189/...

Is there a better way to delete thermostats from themal zones in OpenStudio?

Thank you, Raghu

Based on your description, your question seems to be similar to this issue. Please take a look and see if the solution h

That is my interpretation as well.

For projects where we do not receive all construction layers, I usually try get information about the different layer ma

Was wondering if someone here know of a good resource that documents the mapping of CBECC-com inputs to corresponding EnergyPlus components that are populated in the back-end?

Any suggestions would be super helpful!

Thanks!

@pflaumingo - That answers my question that there is not specific document that has this info. I didn't look at the reve

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CBECC-com inputs mapping to E+ inputs Was wondering if someone here know of a good resource that documents the mapping o

You can create a simple tool to the update the gbXML from openstudio to the format that you desire. You can use any scri

To answer your question - I had some projects in the past that had several zones (over 100+) that fit these exception. I

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Did you check all the other loads for the space - Lighting, occupancy (if any), infiltration (if any), outside air suppl

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I simply use excel to go through the input XML file and populate/repopulate fields based on project specific values. Sin

I simply use excel to go through the input XML file and populate/repopulate fields based on project specific values. Sin

Can you check if the issues reported in these questions solves your issue? https://unmethours.com/question/13399/openst

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Once you run a model with HVACTemplate objects, it is a good idea to verify the inputs in the expidf to make sure that t

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Hi @Hannes The situation in the question that you referenced does not apply to your building as you do not have two ai

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Could you explain the system that you are trying to model and how you intend to control it?

To be precise, that depends on your specific project requirements. Although, lighting schedules usually correspond to oc

I usually input input occupancy as number of people (reflecting peak occupancy). Technically it shouldn't matter how you

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Glad you were able to fix your issue!

@surajtalele That is correct. Although 9.5 people cannot occupy a space at a given time practically, this would account

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@surajtalele are you referring to the table with metabolic rates for various activities to be used in the "People" objec

Hi @antonszilasi From the screenshot, it appears that the source of heating in your model is natural gas (and not steam

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