A thermal conditioning device of a space

The invention relates to a refrigerant fluid circuit comprising a first heat exchanger (1) forming a condenser, a second heat exchanger (2) forming a condenser or an evaporator, a third heat exchanger (3) forming an evaporator, a compressor (C), a first expansion device (D1), a second expansion device (D2) and means (V1, V2, AR) capable of circulating the refrigerant fluid according to a first operating mode in which the refrigerant fluid circulates according to a first loop passing through at least successively the compressor (C), the first heat exchanger (1), the second heat exchanger (2) then forming a condenser, the second expansion device (D2), and the third heat exchanger (3) before passing through the compressor (C) again.