Hot Water Supply Device

Abstract

A hot water supply device ( 1 ) includes a hot water storage tank ( 11 ) and a refrigerant circuit ( 20 ) of a vapor compression refrigeration cycle including a radiator ( 21 ), an evaporator ( 22 ), and an auxiliary evaporator ( 23 ). High-temperature water is retained in the hot water storage tank ( 11 ) in such a manner that storage water taken out from the lower part of the hot water storage tank ( 11 ) is heated in the radiator ( 21 ) to be high-temperature water and is then returned to the upper part of the hot water storage tank ( 11 ). A cooling circuit ( 15 ) is connected to the lower part of the hot water storage tank ( 11 ) so that the storage water in the lower part of the hot water storage tank ( 11 ) is cooled in the auxiliary evaporator ( 23 ) of the refrigerant circuit ( 20 ) and is then returned to the lower part of the hot water storage tank ( 11 ).

1 . A hot water supply device comprising:
 a refrigerant circuit ( 20 ) of a vapor compression refrigeration cycle including a radiator ( 21 ) and an evaporator ( 22 );   a hot water storage tank ( 11 ) for storing high-temperature water heated in the radiator ( 21 ), the hot water storage tank ( 11 ) including a lower part connected to the radiator ( 21 ) through an extraction pipe ( 13 ) and an upper part connected to the radiator ( 21 ) through a return pipe ( 14 ), the hot water supply device supplying heat accumulated in the hot water storage tank ( 11 ) to a user side;   an auxiliary evaporator ( 23 ) provided in the refrigerant circuit ( 20 ); and   a cooling circuit ( 15 ) connected to the lower part of the hot water storage tank ( 11 ) for allowing storage water in the lower part of the hot water storage tank ( 11 ) to be cooled in the auxiliary evaporator ( 23 ) and returning it to the lower part of the hot water storage tank ( 11 ).   
   
   
       2 . A hot water supply device comprising:
 a refrigerant circuit ( 20 ) of a vapor compression refrigeration cycle including a radiator ( 21 ) and an evaporator ( 22 );   a hot water storage tank ( 11 ) for storing high-temperature water heated in the radiator ( 21 ), the hot water storage tank ( 11 ) including a lower part connected to the radiator ( 21 ) through an extraction pipe ( 13 ) and an upper part connected to the radiator ( 21 ) through a return pipe ( 14 ), the hot water supply device supplying heat accumulated in the hot water storage tank ( 11 ) to a user side; and   an auxiliary evaporator ( 23 ) provided in the refrigerant circuit ( 20 ) for cooling storage water flowing into the extraction pipe ( 13 ) from the hot water storage tank ( 11 ).   
   
   
       3 . The hot water supply device of  claim 1 ,
 wherein the auxiliary evaporator ( 23 ) is connected in series to the evaporator ( 22 ) and is arranged downstream of the evaporator ( 22 ).   
   
   
       4 . The hot water supply device of  claim 3 ,
 wherein the refrigerant circuit ( 20 ) includes:
 a bypass circuit ( 28 ) connected to an upstream side and a downstream side of the auxiliary evaporator ( 23 ); and 
 switching means ( 51 ) for switching the refrigerant circuit ( 20 ) so as to allow all refrigerant flowing out from the evaporator ( 22 ) to flow into the bypass circuit ( 28 ) according to the temperature of the refrigerant flowing out from the evaporator ( 22 ). 
   
   
   
       5 . The hot water supply device of  claim 1 ,
 wherein the auxiliary evaporator ( 23 ) is connected in parallel to the evaporator ( 22 ).   
   
   
       6 . The hot water supply device of  claim 1 , further comprising:
 defrosting operation means ( 52 ) for defrosting the evaporator ( 22 ) with the use of heat of the storage water obtained in the auxiliary evaporator ( 23 ).   
   
   
       7 . The hot water supply device of  claim 1 ,
 wherein the refrigerant of the refrigerant circuit ( 20 ) is carbon dioxide.   
   
   
       8 . The hot water supply device of  claim 2 ,
 wherein the auxiliary evaporator ( 23 ) is connected in series to the evaporator ( 22 ) and is arranged downstream of the evaporator ( 22 ).   
   
   
       9 . The hot water supply device of  claim 8 ,
 wherein the refrigerant circuit ( 20 ) includes:
 a bypass circuit connected to an upstream side and a downstream side of the auxiliary evaporator ( 23 ); and 
 switching means ( 51 ) for switching the refrigerant circuit ( 20 ) so as to allow all refrigerant flowing out from the evaporator ( 22 ) to flow into the bypass circuit ( 28 ) according to the temperature of the refrigerant flowing out from the evaporator ( 22 ). 
   
   
   
       10 . The hot water supply device of  claim 2 ,
 wherein the auxiliary evaporator ( 23 ) is connected in parallel to the evaporator ( 22 ).   
   
   
       11 . The hot water supply device of  claim 2 , further comprising:
 defrosting operation means ( 52 ) for defrosting the evaporator ( 22 ) with the use of heat of the storage water obtained in the auxiliary evaporator ( 23 ).   
   
   
       12 . The hot water supply device of  claim 2 ,
 wherein refrigerant of the refrigerant circuit ( 20 ) is carbon dioxide.   
   
   
       13 . A hot water supply device comprising:
 a refrigerant circuit ( 20 ) of a vapor compression refrigeration cycle including a radiator ( 21 ) and an evaporator ( 22 );   a hot water storage tank ( 11 ) for storing high-temperature water heated in the radiator ( 21 ), the hot water storage tank ( 11 ) including a lower part connected to the radiator ( 21 ) through an extraction pipe ( 13 ) and an upper part connected to the radiator ( 21 ) through a return pipe ( 14 ); and   a user side circuit ( 39 ) including:
 a primary side circuit ( 32 ) connected to the upper part and the lower part of the hot water storage tank ( 11 ); 
 an intermediate heat exchanger ( 33 ) connected to the primary side circuit ( 32 ); and 
 a secondary side circuit ( 34 ) which is connected to the intermediate heat exchanger ( 33 ), in which a heating medium circulates, and which supplies the heating medium heat exchanged with the high-temperature water of the hot water storage tank to a user side, 
   wherein the secondary side circuit ( 34 ) of the user side circuit ( 39 ) includes cooling means ( 40 ) provided upstream of the intermediate heat exchanger ( 33 ) for cooling the heating medium.   
   
   
       14 . The hot water supply device of  claim 13 ,
 wherein the cooling means ( 40 ) is a ventilation heat exchanger ( 40 ) for heating outdoor air (OA) supplied indoors.   
   
   
       15 . The hot water supply device of  claim 13 ,
 wherein refrigerant of the refrigerant circuit ( 20 ) is carbon dioxide.