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Temperature and humidity in design builder

asked 2018-03-09 06:57:58 -0500

andreea's avatar

updated 2018-03-11 10:56:41 -0500

i have a building with heated floor and when i run the simulations the temperature and humidity are not constant in the same summer/winter week design. so in the summer i have temperatures between 20-40 deg and a humidity between 40-70% and in the winter the temperatures are between 19-20 deg and humidity between 9-15%

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answered 2018-03-09 10:40:43 -0500

mikesweeney's avatar

it sounds like you have a heating setpoint of 20, but either no cooling setpoint or no cooling equipment assigned to your zones, which means during cooling season temperatures will float between 20-40. likewise, if you don't have any cooling equipment there's no way to control humidity during cooling season. if you put cooling equipment into your zones, you'll also have to assign a humidistat (and if you're using an air loop, use a humidity-related setpoint manager) in order to control for humidity.

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answered 2018-03-13 05:26:47 -0500

andreea's avatar

Thanks for the reply! For the project I have a heating and cooling system in the floor and the heat part I have in the program, but I do not know how to add the cooling part and I think this is the main cause of the big temperature differences.

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does the floor cooling system have chilled water? if so, you'd need to have a chilled water plant connected to it. if you send me the designbuilder model i can take a look.

mikesweeney's avatar mikesweeney  ( 2018-03-14 08:41:06 -0500 )edit

yes it has, but the idea is that it does not let me put the cooling system in the floor and also the underfloor heating (pipes). so I put the cooling system in the ceiling, although that's not what I need and anyway it generates too many errors. I would like to send the model but I do not know how, so if you have an ideea i will do it

andreea's avatar andreea  ( 2018-03-14 09:47:11 -0500 )edit

i'm not sure about cooling in the floor, but designbuilder 5.2 has a "radiant surface" component you could try. or look here for advice on how to model chilled ceiling. you may then have to do a workaround and/or some post processing to get it to represent the differences in stratification properly.

mikesweeney's avatar mikesweeney  ( 2018-03-15 09:53:05 -0500 )edit

thank you for your help!

andreea's avatar andreea  ( 2018-03-16 02:51:07 -0500 )edit

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Asked: 2018-03-09 06:57:58 -0500

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Last updated: Mar 13 '18