Hi @MingboPeng thx for reply. I have used exactly the example you showing, considering to model it using the object “Central Heat Pump System” and definitions of the reference guide, only water cooled solutions seem to be allowed. The unit I’m modeling is air cooled: I forced the input using the “temperature source” object (to consider the real temperatures entering in the condenser/evaporator) I’m wondering what happens when external temperatures go below zero.
Generaly this is the scheme:
And generale description of the system:
The multipurpose 4-pipe units have been made for applications with 4 pipe terminals, e.g. shopping centres, offices or facilities with large windows where there can be the simultaneous demand for hot and cold water with a system which does not require season changeover and therefore is a valid alternative to traditional systems based on the chiller-boiler combination.
PRODUCTION OF COOLED WATER ONLY
The multipurpose unit acts as a classical refrigerator: cool water to the system and condensation heat disposal outside through finned coils.
PRODUCTION OF HOT WATER ONLY
The multipurpose unit acts as a heat pump, exploiting the heat of the outside air, through the finned coil (evaporator) it raises the temperature of the water to be sent to the system through a plate heat exchanger (condenser). The main difference from traditional cycle reverse heat pumps is that the heated water is produced in different heat exchanger from the one used to produce cold water. This separates the two hot-cold sections required for 4-pipe systems.
HEAT RECOVERY MODE
If the utility requires simultaneous hot and cold water, the unit acts as a water heat pump, controlling condensation and evaporation on two distinct plate heat exchangers associated to circulation of cold and hot water in the system.
It automatically changes from one configuration to another to optimise the spent energy depending on the demand by the utility.
Also I’m in doubt about the input of the field “Number of the chiller heater modules”. I’m considering a system based on a single standard unit (EU market). I’d fill the field with 1.
Probably I’m confused because of the diagram in the reference guide that shows a solution made of three modules (but I suppose it is to explain the typical configuration made of more than one module). Anyway I want just to make sure the term “module” is referred to the “packaged unit”(able to work stand-alone) and not to internal components (e.g. number of circuits/compressors).
I appreciate your help
Thx,
Massimiliano