Re: [TRNSYS-users] outlet temperature, water to water heat pump

[knut.erik.enerstvedt@niva.no]

Mavi and David,

A heat pump with a variable speed compressor can fix the
outlet temperature, but they are not very common yet. I once thought I
had to model such a heat pump, so I made some modifications to Type 668
water-water heat pump to include a set point on outlet load temperature,
similar to Type 666 water cooled chiller which has a set point temperature
on the chilled water stream. It was hard to find data on part load performance,
however. Later I found out that I did not need this model after all.

Mavi, let me know if you need more information about the
modified heat pump component.


Best regards,
Knut Erik Enerstvedt
 

>Mavi,
> Heat pumps can't really do that - they are either on and operating
at whatever capacity they have available given the entering water >conditions
or they are off. Unless they are multistage heat pumps, they can't load
follow and provide a constant outlet temperature >regardless of the
inlet temperature. In reality and in simulation, you would have to look
for a method of actually doing that. One thing >you could try is to
have a bypass valve upstream of the heat pump, oversize the heat pump so
that it can always heat or cool the >liquid enough and then divert some
of the upstream liquid around the heat pump and mix it back in downstream
like a tempering >valve.
>Best, 
> David


>Mavi Cambronero Vázquez wrote: 
>Hi everybody!!
 
>I´d like to get a fixed outlet temperature from a
water-water heat pump. Do you know how to do it???
 
>Thank you!!!
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