Heat pump heating system

Abstract

A heat pump heating system ( 1 A) includes: a refrigerant circuit ( 3 ) including a compressor ( 21 ), a radiator ( 22 ), and an expansion member ( 25 A), and an evaporator ( 26 ); a circulation path ( 5 ) for circulating a liquid through the radiator ( 22 ) to produce a heated liquid; and a heater ( 4 ) for dissipating heat of the heated liquid. The refrigerant circuit ( 3 ) is provided with an internal heat exchanger ( 23 A) for transferring heat from a high pressure refrigerant that has released heat in the radiator ( 22 ) to a low pressure refrigerant. The liquid flowing through the circulation path ( 5 ) is cooled in a liquid cooling heat exchanger ( 24 ) by means of the high pressure refrigerant flowing out of the internal heat exchanger ( 23 A), before the liquid flows into the radiator ( 22 ).

1 . A heat pump heating system comprising:
 a refrigerant circuit including a compressor for changing a low pressure refrigerant to a high pressure refrigerant, a radiator for allowing the high pressure refrigerant to release heat, an expansion member for changing the high pressure refrigerant to the low pressure refrigerant, and an evaporator for allowing the low pressure refrigerant to absorb heat;   a circulation path for circulating a liquid through the radiator to produce a heated liquid;   a heater for dissipating heat of the heated liquid;   an internal heat exchanger, provided in the refrigerant circuit, for transferring heat from the high pressure refrigerant that has released heat in the radiator to the low pressure refrigerant; and   a liquid cooling heat exchanger for cooling the liquid flowing through the circulation path by means of the high pressure refrigerant flowing out of the internal heat exchanger, before the liquid flows into the radiator.   
     
     
         2 . The heat pump heating system according to  claim 1 , wherein the liquid flowing into the liquid cooling heat exchanger has a higher temperature than the high pressure refrigerant flowing into the liquid cooling heat exchanger. 
     
     
         3 . The heat pump heating system according to  claim 1 , wherein the internal heat exchanger is designed to exchange heat between the high pressure refrigerant flowing out of the radiator and the low pressure refrigerant flowing out of the evaporator. 
     
     
         4 . The heat pump heating system according to  claim 1 , wherein the internal heat exchanger is designed to exchange heat between the high pressure refrigerant flowing out of the radiator and the low pressure refrigerant before flowing into the evaporator. 
     
     
         5 . The heat pump heating system according to  claim 1 , wherein the expansion member is an expansion valve, an expander for recovering power from the expanding refrigerant, or an ejector. 
     
     
         6 . The heat pump heating system according to  claim 1 , wherein the circulation path includes a supply pipe for introducing the liquid from the heater to the liquid cooling heat exchanger, an intermediate pipe for introducing the liquid from the liquid cooling heat exchanger to the radiator, and a recovery pipe for introducing the liquid in the form of the heated liquid from the radiator to the heater. 
     
     
         7 . The heat pump heating system according to  claim 1 , wherein
 the circulation path includes a tank for storing the heated liquid, a supply pipe for introducing the liquid from the tank to the liquid cooling heat exchanger, an intermediate pipe for introducing the liquid from the liquid cooling heat exchanger to the radiator, and a recovery pipe for introducing the liquid in the form of the heated liquid from the radiator to the tank, and   the heat pump heating system further comprises:
 a feed pipe for feeding the heated liquid stored in the tank to the heater; and 
 a return pipe for returning the heated liquid that has released heat in the heater to the tank. 
   
     
     
         8 . The heat pump heating system according to  claim 1 , wherein
 the circulation path includes a tank for storing the heated liquid, a supply pipe for introducing the liquid from the tank to the liquid cooling heat exchanger, an intermediate pipe for introducing the liquid from the liquid cooling heat exchanger to the radiator, and a recovery pipe for introducing the liquid in the form of the heated liquid from the radiator to the tank, and   the heat pump heating system further comprises:
 an in-tank heat exchanger, disposed in the tank, for heating a heat carrier by means of the heated liquid stored in the tank; 
 a feed pipe for feeding the heat carrier that has been heated in the in-tank heat exchanger to the heater; and 
 a return pipe for returning the heat carrier that has released heat in the heater to the in-tank heat exchanger. 
   
     
     
         9 . The heat pump heating system according to  claim 7 , wherein
 the liquid is water,   the heated liquid is hot water, and   the heat pump heating system further comprises:
 a water inlet pipe for supplying tap water to the tank; and 
 a hot water outlet pipe for withdrawing the hot water from the tank. 
   
     
     
         10 . The heat pump heating system according to  claim 6 , wherein the circulation path further includes a bypass pipe for connecting the supply pipe and the intermediate pipe, and a switching member for switching between a circulation of the liquid not through the bypass pipe and a circulation of the liquid through the bypass pipe. 
     
     
         11 . The heat pump heating system according to  claim 10 , wherein
 the supply pipe is provided with a temperature sensor for detecting the temperature of the liquid flowing into the supply pipe, and   the heat pump heating system further comprises a controller for controlling the switching member so that the liquid is circulated through the bypass pipe when the temperature of the liquid detected by the temperature sensor is lower than a predetermined temperature and that the liquid is circulated not through the bypass pipe when the temperature of the liquid detected by the temperature sensor is equal to or higher than the predetermined temperature.   
     
     
         12 . The heat pump heating system according to  claim 1 , wherein the refrigerant is carbon dioxide. 
     
     
         13 . The heat pump heating system according to  claim 7 , wherein the circulation path further includes a bypass pipe for connecting the supply pipe and the intermediate pipe, and a switching member for switching between a circulation of the liquid not through the bypass pipe and a circulation of the liquid through the bypass pipe. 
     
     
         14 . The heat pump heating system according to  claim 8 , wherein the circulation path further includes a bypass pipe for connecting the supply pipe and the intermediate pipe, and a switching member for switching between a circulation of the liquid not through the bypass pipe and a circulation of the liquid through the bypass pipe.