Method for thermal conditioning of a passenger compartment of a motor vehicle

The invention relates to a method for thermal conditioning of a passenger compartment of a motor vehicle using a refrigerant fluid circulation circuit comprising at least a first heat exchanger (1) capable of forming a condenser and/or an evaporator, a second heat exchanger (2) capable of forming a condenser, a third heat exchanger (3) capable of forming an evaporator, a compressor (5), a first expansion device (D1), a second expansion device (D2), and means (V1, V2, P1 to P8) capable of directing the refrigerant fluid. The invention particularly defines the opening laws of the expansion devices (D1, D2).