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Problem about Radiant Cooling system that doesn't have Cooling rate and Mass flow

I made a system with low temperature radiant ceiling and Heat exchanger desiccant system. Heat exchanger desiccant operated with a DX cooling coil for dehumidify and cooling, this is the HVAC air system served as a secondary cooling device at summer and radiant system is the plant loop which served as a primary cooling device at summer. Thermostats were set as 26 degree at summer. The cooling control temperature schedules were also set as 26 degree at summer. Air Terminal :Single duct :uncontrolled worked as HVAC air system's terminal. Desiccant + DX cooling coil + terminal machine are operated with low temperature radiant system while Air Terminal :Single duct :uncontrolled is combined with radiant system in the Zone HVAC :Equipment list. I compared with example files when established this system. I guess my system is same as the example file, so I cannot understand why my radiant system don't have the cooling rate. I've been struggling with this problem for one month, so I need your help. I have no other ideas to solve this problem. Thanks for your attention and looking forward your help. Welcome everybody to comment. The attachment is my case. The IDF file picture of my case is following. Please refer to this.image description image description image descriptionC:\fakepath\1.PNG C:\fakepath\2.PNG C:\fakepath\3.PNG

liu shuo's avatar
31
liu shuo
asked 2019-08-21 21:36:21 -0500
__AmirRoth__'s avatar
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__AmirRoth__
updated 2019-09-29 10:17:21 -0500
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Well, the low temperature radiant system has its own control and does not rely on a thermostat. That would be the first thing I would check. Just make sure the radiant system works without the air side.

You can add air side later since the water side is where most errors occurs.

Viper's avatar
61
Viper
answered 2019-08-22 16:29:35 -0500
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Thank you for your answer. I'm sure that the radiant system has its own temperature and humidity control thermostat. And the Zone Thermostat is set to control the air system. From your comment, I guess that you mean I should build the water loop(radiant system) firstly and then add the air loop? Right? Sorry for my late reply. And thanks again for your help.

liu shuo's avatar liu shuo (2019-08-27 19:17:18 -0500) edit

I had built only a Radiant system for this building(without Air loop case) . But the same problem occurred. There was no cooling and heating rate for radiant system. When I set this case, I've compared with Example file. So I wonder why my system has no cooling and heating rate under the same setting condition. (T_T)

liu shuo's avatar liu shuo (2019-08-27 23:45:36 -0500) edit

I remember I had the same problem when I build a low temperature radiant system but forgot how I solved it. Have you take a look at the RadLoTempHydrHeatCool.idf?

Viper's avatar Viper (2019-08-28 00:02:37 -0500) edit

Yeah, my case is almost the same setup as this example idf. So I'm confused. If possible,can I know your e-mail? I want to sent my .idf file to you. It's more convenience than these capture picture. Although it was rude, but I didn't have anyone to ask around me. Thank you very much

liu shuo's avatar liu shuo (2019-08-28 00:59:09 -0500) edit

yeah, sure. My email is peng.shi@stonybrook.edu.

I just recalled the problem I had before. I didn't modify the surface where the radiant panels are located. Therefore the radiant panels do not sense the temperature. You need to make sure you change the Outside Boundary Condition and Outside Boundary Condition Object.

Viper's avatar Viper (2019-08-28 13:50:06 -0500) edit
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