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Radiant Ceiling and Floor

asked 2016-07-20 08:00:03 -0600

João Rodrigues gravatar image

updated 2017-05-08 18:35:52 -0600


I have a model with 2 low temperature radiant systems, one on the floor and the other on the ceiling, their specific flow is different. So I can’t create just one system and associate it to the radiant surface type as CeilingsAndFloors.

I have created 2 internal source constructions, one for the floor and other for the ceiling, so I could have two systems.

However, when I run the simulation it fails, by the result of a severe error that says:

* Severe * Surface SURFACE 1 is referenced by more than one radiant system--this is not allowed

* Fatal * GetLowTempRadiantSystem: Errors found in input. Preceding conditions cause termination.

How can I define, for example, that surface 1 has the system of the floor heating, and surface 2 has the system of the ceiling heating. Thanks,

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answered 2016-07-20 09:24:33 -0600

updated 2016-07-20 10:08:58 -0600

If you are working in native EnergyPlus (e.g. using IDF Editor), it's a simple matter of setting the 'Surface Name or Radiant Surface Group Name' for each system to the correct internal source construction surface.

If you're using OpenStudio, however (which you seem to be, based on the mention of 'CeilingsAndFloors'), it's somewhat trickier. I've documented an issue with forward translation for this object whereby none of the 'Radiant Surface Type' inputs will translate to EnergyPlus input with only ceiling surfaces listed in the Radiant Surface Group Name.

What you should be able to do is have one system with Radiant Surface Type = "Ceilings" which would translate to an object that references the internal source construction ceiling surfaces, and one with Radiant Surface Type = "Floors" that does the same for floors (as you describe). The fact that you still get the error that a surface is referenced by more than one system indicates to me that my issue is still valid ("Ceilings" setting actually translates to ceilings and floors). Until this gets fixed, I think you're limited to editing the idf (see here) or writing an EnergyPlus measure.

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Yes I am using OpenStudio. Thank you for the explanation Eric.

João Rodrigues gravatar image João Rodrigues  ( 2016-07-20 10:43:55 -0600 )edit

@Eric Ringold Has this problem been resolved for OS 2.3? I am getting the following error, where Surfaces 415 and 459 are adjacent surfaces.

* Severe * Surface SURFACE 415 is referenced by more than one radiant system--this is not allowed * Severe * Interzone surface SURFACE 459 is referenced by more than one radiant system--this is not allowed

ethankheil gravatar image ethankheil  ( 2017-11-07 16:45:27 -0600 )edit

@ethankheil it should be fixed. Are those surfaces a ceiling/floor pair? What are you specifying for 'Radiant Surface Type'?

Eric Ringold gravatar image Eric Ringold  ( 2017-11-07 16:52:38 -0600 )edit

@Eric Ringold I am having this problem in energyplus 8.9. As far as I can tell, the heated floor ZoneHVAC:LowTemperatureRadiant:VariableFlow objects and cooled ceiling ZoneHVAC:LowTemperatureRadiant:VariableFlow objects access different BuildingSurface:Detailed objects and different Construction:InternalSource objects. I don't really know what I'm doing though, so likely it's a simple fix.

Do you have an example file with heated radiant floors and cooled radiant ceilings (both sides of paired floor ceiling surfaces) on hand that I could compare against?

P.S. See below answer.

mldichter gravatar image mldichter  ( 2018-10-04 19:24:22 -0600 )edit

answered 2018-10-05 18:11:19 -0600

mldichter gravatar image

I was able to get rid of this error by changing the surface to Adiabatic. See this post for more details and an example file.

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Asked: 2016-07-20 08:00:03 -0600

Seen: 1,171 times

Last updated: Oct 05 '18