Heat pumps

Claim 1

A HEAT PUMP COMPRISING A REFRIGERANT COMPRESSOR; A FLUID HEATING CONDENSER; A FLUID COOLING EVAPORATOR; AN OUTDOOR HEAT EXCHANGER; ACCUMULATOR MEANS; A HEAT EXCHANGE COIL ARRANGED TO HEAT LIQUID WITHIN SAID ACCUMULATOR MEANS; A MAIN EXPANSION VALVE; A THERMAL EXPANSION VALVE; A SUCTION GAS LINE CONNECTING SAID ACCUMULATOR MEANS TO THE SUCTION SIDE OF SAID COMPRESSOR; MEANS WHEN THE COOLING LOAD ON SAID EVAPORATOR IS GREATER THAN THE HEATING LOAD ON SAID CONDENSER, FOR CAUSING REFRIGERANT TO FLOW IN A FIRST CIRCUIT IN WHICH DISCHARGE GAS FROM SAID COMPRESSOR IS DIRECTED INTO SAID EXCHANGER, IN WHICH CONDENSED REFRIGERANT FROM SAID EXCHANGER IS DIRECTED THROUGH SAID COIL AND THEN THROUGH SAID MAIN EXPANSION VALVE INTO SAID EVAPORATOR, AND IN WHICH GAS AND UNEVAPORATED REFRIGERANT IS DIRECTED FROM SAID EVAPORATOR INTO SAID ACCUMULATOR MEANS; MEANS WHEN ADDITIONAL HEATING IS REQUIRED WHILE SAID COOLING LOAD IS GREATER THAN SAID HEATING LOAD, AND WHEN SAID HEATING LOAD IS GREATER THAN SAID COOLING LOAD, FOR CAUSING SAID REFRIGERANT TO FLOW IN A SECOND CIRCUIT IN WHICH DISCHARGE GAS FROM SAID COMPRESSOR IS DIRECTED INTO SAID CONDENSE, IN WHICH CONDENSED REFRIGERANT FROM SAID CONDENSER IS DIRECTED INTO SAID COIL, IN WHICH REFRIGERANT FROM SAID COIL IS DIRECTED THROUGH SAID MAIN EXPANSION VALVE INTO SAID EXCHANGER AND INTO SAID EVAPORATOR, IN WHICH REFRIGERANT FROM SAID CONDENSER IS DIRECTED THROUGH SAID THERMAL EXPANSION VALVE INTO SAID EVAPORATOR WHEN THE REFRIGERANT DIRECTED THROUGH SAID MAIN EXPANSION VALVE INTO SAID EVAPORATOR IS INSUFFICIENT TO PREVENT THE LATTER FROM BECOMING STARVED, IN WHICH GAS AND UNEVAPORATED REFRIGERANT IS DIRECTED FROM SAID EXCHANGER AND FROM SAID EVAPORATOR INTO SAID ACCUMULATOR MEANS; MEANS RESPONSIVE TO SUPERHEAT IN THE GAS LEAVING SAID EVAPORATOR FOR ADJUSTING SAID THERMAL EXPANSION VALVE; AND MEANS FOR ADJUSTING SAID MAIN EXPANSION VALVE TO METER ALL OF THE REFRIGERANT WHICH IS CONDENSED LESS THAN METERED BY SAID THERMAL EXPANSION VALVE.