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Hi! Does anyone know how can I model a technical floor in designbuilder and how can I add a LECU?

asked 2018-05-02 07:27:20 -0500

andreea's avatar

updated 2018-05-02 11:17:32 -0500

I need to add a LECU( Local Environmental Control Unit) in my model.

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If in understand correctly what you want to model is more often called a "Raised Floor", with "Underfloor Air Distribution" (UFAD). There are examples of such systems in EnergyPlus Examples/ directory, and other questions on this site may help too:

Julien Marrec's avatar Julien Marrec  ( 2018-05-02 07:45:58 -0500 )edit

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answered 2018-05-07 08:50:23 -0500

andreea's avatar

updated 2018-05-09 02:39:13 -0500

thank you for your answers! the idea is that I have both technical floor space and heating and cooling in the concrete slab. so I designed a system in builder design, but I do not think it's correct because it gives me error when simulating: zone is specified as having a radiant surface but no radiant surface in the zone have an internal source set in their constructionimage descriptionimage description

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I left the same hvac system but I put the internal source in two different places and these are the errors. The first section is right for my model but I have those errors.I read in the manual that to make a plenum I have to replace the splitter/mixer with the supply plenum/return plenum ,which I have done. On the floor void writes that: if the floor construction already has an air gap for the floor void and its thickness is used to define the inner volume then you should enter 0 here. (I do not know if it considered floor void the air gap that i left in construction)

andreea's avatar andreea  ( 2018-05-09 02:37:37 -0500 )edit

answered 2018-05-04 04:50:12 -0500

kksharma3951's avatar

to add technical floor or false ceiling, they best way to do is by making a new zone and selecing it as an plenum or you can also model it by using floor void in construction tab.

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I designed the plenum part and after that i took the picture above and the errors.

andreea's avatar andreea  ( 2018-05-07 09:17:28 -0500 )edit

Can you share the screenshot of the error? i am guessing you need to activate internal source from construction tab. Generally when you have any radiant source for heating/cooling the internal source needs to be activated. Refer to slide number 40-46 from the link below:

kksharma3951's avatar kksharma3951  ( 2018-05-09 01:19:21 -0500 )edit

I could just add the photo above, I hope you understand. So what the project ask me to do is the following: I have the concrete slab inside which I have the heat and cooling source, then I have an air gap for the recirculated air coils heated and cooled by the preference through convective systems by and through floor(thats why i think the firs section is the correct one). This system also incorporates the fresh air supply system through the floor. The fresh air that is distributed inside the building is produced in recovery CTAs temperature and humidity.

andreea's avatar andreea  ( 2018-05-09 02:46:27 -0500 )edit

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Asked: 2018-05-02 07:27:20 -0500

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Last updated: May 09 '18