Heat pump unit and method for cooling and/or heating by means of said heat pump unit

Abstract

A heat pump unit ( 1 ) comprising at least one circuit ( 2 ) adapted to perform a heat pump cycle with a respective operating fluid, which comprises: an evaporator (S 8 ) adapted to perform the evaporation of the operating fluid at a lower pressure of said heat pump cycle and intended to be connected to an external circuit of a first thermal user installation in a cooling operating mode of said heat pump unit; a condenser (S 4 ) adapted to perform the condensation of the operating fluid at a higher pressure of said heat pump cycle and intended to be connected to an external circuit of a heat sink ( 20 ) in a cooling operating mode of said heat pump unit ( 1 ), and a first heat exchanger (S 6 ), adapted to perform an undercooling of the operating fluid at the higher pressure of said heat pump cycle after the condensation of the same. The first heat exchanger (S 6 ) is selectively connectable to an external circuit of a second thermal user installation ( 12 ) for transferring thereto heat power released by said operating fluid during said undercooling. The invention further relates to a method for cooling and/or heating which may be implemented by means of the heat pump unit ( 1 ).

1 . Heat pump unit comprising at least one circuit adapted to perform a heat pump cycle with a respective operating fluid, said at least one circuit comprising:
 an evaporator adapted to perform the evaporation of the operating fluid at a lower pressure of said heat pump cycle and intended to be connected to an external circuit of a first thermal user installation in a cooling operating mode of said heat pump unit;   a condenser adapted to perform the condensation of the operating fluid at a higher pressure of said heat pump cycle and intended to be connected to an external circuit of a heat sink in a cooling operating mode of said heat pump unit, and   a first heat exchanger, adapted to perform an undercooling of the operating fluid at the higher pressure of said heat pump cycle (HPCM) after the condensation of the same,   
       characterized in that said first heat exchanger is selectively connectable to an external circuit of a second thermal user installation for transferring thereto heat power released by said operating fluid during said undercooling, said unit comprising switching means, adapted to allow an exchange of connections of the external circuits of said first thermal user installation and of said first heat sink with said evaporator and with said condenser, respectively. 
     
     
         2 . Heat pump unit ( 1 ) according to  claim 1 , wherein said circuit comprises a first sub-circuit adapted to perform a higher temperature heat pump cycle with a respective operating fluid and a second sub-circuit adapted to perform a lower temperature heat pump cycle with a respective operating fluid, wherein said first and second sub-circuits are in cascading heat exchange relationship with each other so as to perform globally a two-stage heat pump cycle, and wherein said condenser is connected in said first sub-circuit and said evaporator and said first heat exchanger are connected in said second sub-circuit. 
     
     
         3 . Heat pump unit according to  claim 2 , wherein said first sub-circuit comprises a second heat exchanger adapted to perform an undercooling of the operating fluid at the higher pressure of said higher temperature heat pump cycle after the condensation of the same and selectively connectable to the external circuit of said second thermal user installation to transfer thereto heat power released during said undercooling by the operating fluid of said higher temperature heat pump cycle. 
     
     
         4 . Heat pump unit according to  claim 1 , wherein at least one of said first heat exchanger and said second heat exchanger in a heating operating mode of said heat pump unit is further selectively connectable to the external circuit of said first heat sink so as to perform a preheating of a heat carrier fluid coming from said heat sink by means of heat power released by the operating fluid of at least one of said lower temperature heat pump cycle and said higher temperature heat pump cycle during the respective undercooling. 
     
     
         5 . Heat pump unit according to  claim 1 , wherein the operating fluid of said heat pump cycle, or the operating fluids of said higher temperature heat pump cycle and of said lower temperature heat pump cycle respectively, are selected from the group consisting of: (E)-2-butene, (Z)-2-butene, 1-butylene, dimethyl ketone, methylacetylene, methyl alcohol, methylpentane, methylpropene, n-hexane, R1270, R8290, R600, R600a, R601, R601a, RE-170, tetramethylmethane or RC-270. 
     
     
         6 . Heat pump unit according to  claim 1 , comprising means for detecting and evacuating gas leaks. 
     
     
         7 . System for cooling/heating environments and/or for producing sanitary hot water comprising a heat pump unit according to  claim 1 . 
     
     
         8 . Method for cooling and/or heating by means of a heat pump unit adapted to perform at least one heat pump cycle with a respective operating fluid, said method comprising, in a cooling operating mode of said heat pump unit, the following steps:
 evaporating said operating fluid at a lower pressure of said heat pump cycle subtracting heat power from a first thermal user installation;   condensing said operating fluid at a higher pressure of said heat pump cycle releasing heat power to a first heat sink;   undercooling said operating fluid at the higher pressure of said heat pump cycle after said step of condensing;
 transferring the heat power released by said operating fluid during said undercooling step to a second thermal user installation.