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Missing required property 'air_inlet_node_name'

asked 2019-12-15 12:41:17 -0500

katmojo's avatar

updated 2022-10-11 08:16:14 -0500


I implemented a HVAC-System in my building with four thermal zones. For that I built an air loop, a hot water loop, a chilled water loop and a condenser loop. Every coil are attached to their water loop. But as I want to run the simulation the following error appears:

Program Version,EnergyPlus, Version 9.2.0-921312fa1d, YMD=2019.12.15 18:30,
** Severe  ** <root>[Coil:Cooling:Water][Coil Cooling Water 1] - Missing required property 'air_inlet_node_name'.
** Severe  ** <root>[Coil:Cooling:Water][Coil Cooling Water 1] - Missing required property 'air_outlet_node_name'.
** Severe  ** <root>[Coil:Heating:Water][Coil Heating Water 1] - Missing required property 'air_inlet_node_name'.
** Severe  ** <root>[Coil:Heating:Water][Coil Heating Water 1] - Missing required property 'air_outlet_node_name'.
**  Fatal  ** Errors occurred on processing input file. Preceding condition(s) cause termination.
...Summary of Errors that led to program termination:
..... Reference severe error count=4
..... Last severe error=<root>[Coil:Heating:Water][Coil Heating Water 1] - Missing required property 'air_outlet_node_name'.
************* Warning:  Node connection errors not checked - most system input has not been read (see previous warning).
************* Fatal error -- final processing.  Program exited before simulations began.  See previous error messages.
************* EnergyPlus Warmup Error Summary. During Warmup: 0 Warning; 0 Severe Errors.
************* EnergyPlus Sizing Error Summary. During Sizing: 0 Warning; 0 Severe Errors.
************* EnergyPlus Terminated--Fatal Error Detected. 0 Warning; 4 Severe Errors; Elapsed Time=00hr 00min  0.45sec

I am a beginner and follow the steps of the book "Building Energy Modeling with OpenStudio" at checkpoint 7.

Does anyone know where the problem is and can help me please?

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I also ran into the same problem as you have described using the same book as you.

Edit: When I removed the VAV hot water reheat coils, and replaced them with electric reheat coils, I was able to run the simulation.

IanVG's avatar IanVG  ( 2022-10-05 14:44:36 -0500 )edit

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answered 2019-12-16 08:04:31 -0500

updated 2022-10-11 06:56:02 -0500

You have a few coils such as Coil:Cooling:Water and Coil:Heating:Water somewhere in your model that are likely connected to a PlantLoop yet they aren't connected to any air-side systems such as an AirLoopHVAC (or a ZoneHVACComponent).

Had you shared your model I could have pinpointed them. In the OS App, go to your PlantLoop(s), and look for Coils on the demand side that aren't connected to anything.

The reciprocal is also very likely. If you have dragged an AirTerminalSingleDuctVAVReheat with a HW coil from the library to your AirLoopHVAC demand side, click on the ATU, go to the "Link" icon, and select the PlantLoop to conect it to.

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I'd like to share my file with you but I don't think I can in a comment. I will share it in an answer so I can share my problem with you.

IanVG's avatar IanVG  ( 2022-10-05 14:49:08 -0500 )edit

answered 2022-10-05 14:50:50 -0500

IanVG's avatar

updated 2022-10-05 15:27:24 -0500

I am having the same problem and as this question was not yet answered, I will post a link to my file here so others can reproduce it. Looks like this website will not accept a .osm file in the answer section, so I will make a sharing link to share this file.

Edit: Here is the .osm file with the same errors as described by OP.

Edit: I was able to fix this error when I replaced the VAV hot water reheat coils with electric reheat coils. The strange behavior is that when I add a VAV reheat coil it appears to add two objects:

  1. VAV HW Rht (i.e. the air-side of the reheat coil)
  2. VAV HW Rht Coil (i.e. the water-side of the reheat coil)

It looks like the hot water coil is not added as an object that I would be able to add to a plant system. This appears to be a bug of some sort. But also, I am not sure if the following air-side & plant-side set-up for a VAV with Reheat makes sense. Why are there two hot water coils for each VAV with Reheat system? Shouldn't there only be one? Maybe someone can help clarify.

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You seem to assume there must be a bug, but there are none. The AirTerminalSingleDuctVAVReheat is the air side component indeed. and it has a CoilHeatingWater that is for connecting to the plant loop. It's not clear if you're using the OSApp or the SDK. In the SDK:

atu = m.getAirTerminalSingleDuctVAVReheats[0]
p = m.getPlantLoops[0]
=> true

In the OSApp, on your AirLoopHVAC view, you click on the ATU, and there's in the right panel a "link" icon that allows you to select a plant loop to connect the coil

Julien Marrec's avatar Julien Marrec  ( 2022-10-11 06:52:59 -0500 )edit

cf image I added in the two years old answer above (The question was answered (with what limited information was given). It just wasn't accepted probably because the user didn't bother)

Julien Marrec's avatar Julien Marrec  ( 2022-10-11 06:56:43 -0500 )edit

Ah, that was it! I am using the Building Energy Modeling with OpenStudio book and I was expecting the same exact behavior for linking the hot water cooling loop as for the VAV reheat loop. Thank you for the help! I see now that some objects require the linkage to other systems via the "link" icon. I appreciate the update on the answer and your work.

IanVG's avatar IanVG  ( 2022-10-11 12:58:47 -0500 )edit

Glad you got it sorted.

Julien Marrec's avatar Julien Marrec  ( 2022-10-12 01:59:37 -0500 )edit

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Asked: 2019-12-15 12:41:17 -0500

Seen: 1,067 times

Last updated: Oct 12 '22