[TRNSYS-users] How to set exiting fluid temperature for an air-water heat pump

[David BRADLEY]

Zhe,
   The answer to your question depends on the way that your system is 
designed. In the real (as opposed to the simulation) world, typically, 
single stage heat pumps do not have any internal control over their 
outlet temperature. Their compressors are either on or off and the 
outlet temperature is dependent only on the inlet and the environmental 
conditions. Any control on outlet temperature would be done using 
thermostats, diverting valves, tempering valves, etc. Type941 models a 
single stage heat pump so any outlet temperature control should be done 
using other Types so as to match the design of the system.

   In recent years, multistage heat pumps and (at least in one 
manufacturer's case) variable speed compressor heat pumps have come on 
the market. These do have some control on outlet temperature. If you are 
trying to model the performance of a heat pump that has a variable speed 
compressor in it, you won't be very well served by using Type941 I am 
afraid. I wrote a model of such a heat pump that is available from a 
specific manufacturer and would be happy to correspond with you about it 
directly if you are interested.
Kind regards,
  David


On 7/6/2012 05:29, Zhe Li wrote:
>
> Dear Trnsys user,
>
> Thanks for your time.
>
> I am currently using air-water heat pump (type 941) for my model. I 
> understand this is a relatively new component in Trnsys, Would be 
> possible if anybody can let me know how to set a limit temperature for 
> the exiting fluid from the heat pump?
>
> Thank you very much in advance,
>
> Zhe Li
>
>
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-- 
***************************
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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