Air-Conditioning System Provided With a Heat Pump

Abstract

The invention relates to an air-conditioning system ( 1 ), in particular a motor vehicle air-conditioning system ( 1 ) comprising a coolant circuit ( 2 ) provided with a coolant compressor ( 3 ) and a gas cooler ( 4 ), an internal heat exchanger ( 5 ), an expansion unit ( 7 ) and an evaporator ( 8 ) Said invention is characterised in that a device for turning back the coolant flow direction is provided for the heal pump operation and means for switching off the internal heat exchanger ( 5 ) when the flow direction is reversed is also provided.

1 . An air conditioning system, in particular a motor vehicle air conditioning system, having a circuit through which refrigerant flows and in which are arranged a refrigerant compressor and a first heat exchanger, an inner heat exchanger, an expansion element and a second heat exchanger, the first heat exchanger serving as a gas cooler in AC operation and the second heat exchanger serving as an evaporator in AC operation, wherein a device for reversing the flow direction of the refrigerant is provided for heat pump operation, and means are provided which deactivate the inner heat exchanger while the flow direction is reversed.  
   
   
       2 . The air conditioning system as claimed in  claim 1 , wherein the means which deactivate the inner heat exchanger while the flow direction is reversed preferably comprise two non-return valves.  
   
   
       3 . The air conditioning system as claimed in  claim 1 , wherein the device for reversing the flow direction of the refrigerant comprises a cross-over circuit of the back pressure and high pressure connections on or in the refrigerant compressor.  
   
   
       4 . The air conditioning system as claimed in  claim 2 , wherein the non-return valves are provided on or in the inner heat exchanger.  
   
   
       5 . The air conditioning system as claimed in  claim 1 , wherein the refrigerant compressor can be operated in two directions or a correspondingly acting configuration of lines and valves is provided.  
   
   
       6 . The air conditioning system as claimed in  claim 1 , wherein an expansion element having antiparallel bypasses is provided in the circuit.  
   
   
       7 . The air conditioning system as claimed in  claim 1 , wherein the heat exchanger which serves as an evaporator in AC operation functions as a heater in heat pump operation.  
   
   
       8 . The air conditioning system as claimed in  claim 1 , wherein CO 2  is used as the refrigerant.  
   
   
       9 . The air conditioning system as claimed in  claim 1 , wherein a compressor regulator valve and a device for switching the refrigerant flow direction are electrically controlled.  
   
   
       10 . The air conditioning system as claimed in  claim 1 , wherein the stroke volume of the refrigerant compressor is adjustable.  
   
   
       11 . A method for operating an air conditioning system as claimed in  claim 1 , the refrigerant flowing through the circuit counter to the normal flow direction, and the inner heat exchanger being bypassed, during heat pump operation.