[TRNSYS-users] Switch between two cooling systems automatically

[David BRADLEY]

Ryan,
   There are (at least) two ways that you can approach this. One way is 
to write some equations using Boolean functions that enable and disable 
the economizer and chiller based on ambient temperature. Please see my 
response earlier today to a post called "Control signal for GSHP" to 
some tips on setting these equations.

   It is slightly different from the control logic you describe but you 
could also make use of the multi stage cooling ability in the Type108 
thermostat model. You could use this model to enable the economizer if 
the zone temperature gets to a certain temperature but then turn off the 
economizer and turn on the chiller if the room temperature continues to 
rise to a second setpoint temperature.
Kind regards,
  David


On 2/7/2014 04:06, Jian Yan wrote:
> Hello dears,
>
> I'm recently building a thermal model of a server room in TRNSYS 17, 
> where two types of cooling systems are applied, chiller and 
> economizer. My goal is to cool the server room by the chiller when the 
> ambient temperature is above 18 centigrade, while using free cooling 
> (economizer) when the temperature is below 18 centigrade.
>
> The chiller system is already built and functional, however, I have no 
> clue how to enable the model switch between the two cooling systems 
> automatically according to the outdoor temperature, like how to set 
> the temperature sensor, valve or other staffs.
>
> Thank you very much in advance.
>
> Best regards,
> Ryan
>
>
>
> _______________________________________________
> TRNSYS-users mailing list
> TRNSYS-users at cae.wisc.edu
> https://mailman.cae.wisc.edu/listinfo/trnsys-users

-- 
***************************
David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
22 North Carroll Street - suite 370
Madison, WI  53703 USA

P:+1.608.274.2577
F:+1.608.278.1475
d.bradley at tess-inc.com

http://www.tess-inc.com
http://www.trnsys.com

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