David,
really thanks, then I go ahead with Type690. I had already considered the type682 (or 693 for an air stream), so i will pay attenction to the difference between a central plant and zonal heat pumps.
Yes, I’m using TRNSYS18. It would be really nice if you let me have an example.
Thank you again.
Kind regards,
Jacopo
Jacopo,
You are on the right track with Type690 and a heat pump. The assumption when generating heating and cooling loads is that the zone temperature is controlled. The idea of Type690 is to impose those loads on a lumped capacitance to turn them back into temperatures
so that you can implement a thermostat that controls a heat pump whose energy addition/removal is also imposed on the lump to try and keep it at a controlled temperature. The key is to tune the lump so that it reacts to the load and the input from the heat
pump in the same way that the original zone does.
Another valid approach would be to use Type682. The idea here is that you impose the heating and cooling loads on a liquid stream. As an aside, there is also Type693 if you want to impose the loads on an air stream. The Type682 solution is ideal if you
are modeling a central plant and if your loads include the energy consumption of the terminal delivery devices. If your heat pumps are zonal then things get a little more tricky and you're not going to use the heat pumps to directly impact the liquid stream.
Instead you're going to give the heat pump the entering water temperature and the control mode (heating or cooling). You're going to use the heat pump's outputs for compressor energy to modify your zone loads. It sounds more complicated than it is and if you
are using v18 I can make you an example of how it might work.
kind regards,
David
On 05/09/2022 04:44, Jacopo Valente via TRNSYS-users wrote:
Dear TRNSYS users,
I am trying to simulate a system for the conditioning of a building, in particular first an air-to-air heat pump system and then a water-to-water heat pump system. In my case I haven’t the building modeling like
using type56, but I have the required loads in both heating and cooling mode. I have the tess library and I tried to connect the heat pump to the type690, but I'm not sure it's the correct choice. Which is the type most suitable for reading the loads and controlling
the zone temperature?
Best regards,
Jacopo
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