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Building modelling in TRNSYS (Type 56) : ASHRAE 2013 Design day as Weather Data for HVAC sizing

asked 2017-05-10 16:06:04 -0600

mhtalb gravatar image

updated 2017-05-24 10:45:00 -0600


I have a building model in TRNSYS that I would like to validate with a model I made with Energy Plus/OpenStudio.

To achieve this, I'd like to know how my TRNSYS model behave for the ASHRAE 2013 Design Day (.ddy file) : heating and cooling loads, temperature and humidity profiles. But there's no Type in TRNSYS that allowed .ddy file in the Weather Date Reading and Processing folder.

Is that even possible? If not, how HVAC sizing is done in TRNSYS without ddy-file?

I'm new to building modelling, any help will be appreciated. Thank you,

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It’s been a while since I used Trnsys, but I don’t remember using design days. I obtained the heating/cooling load by running the model for all year (using ideal conditions) and I extracted the maximum values from an excel file. Then I designed the HVAC equipment based on those maximum values.

banicu gravatar image banicu  ( 2017-05-11 08:17:27 -0600 )edit

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answered 2017-05-11 08:17:19 -0600

Tim McDowell gravatar image

TRNSYS does not perform automatic sizing of equipment and so does not have a mechanism for using a design day weather file. Typically sizing is done by activating ideal heating and cooling in the building model and printing the zone loads for the year. The maximum heating and cooling loads for the zones can be used to determine the equipment size. Then the full HVAC system model can be created in the TRNSYS project and the zone temperatures can be checked versus the setpoints to determine if the equipment size is adequate. If you feel that using the standard weather file is not adequate for your situation, there are programs available that create extreme annual weather files that can be read by TRNSYS.

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Asked: 2017-05-10 16:05:34 -0600

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Last updated: May 11 '17