A device for producing refrigeration to a temperature Tf of less than -20°C, from a heat source at a temperature Th of the order of the 60-80°C and a heat sink at room temperature To of the order of 10°C to 25°C, comprising a refrigerating dipole D2 and an auxiliary dipole D1, characterized in that: • the thermochemical phenomena in the dipole D2 are such that this dipole may produce refrigeration at Tf with a heat sink at room temperature To; • the thermochemical phenomena in the dipole D1 are such that this dipole may be regenerated from the heat source Th and a heat sink at temperature To; • D1 comprises an evaporator/condenser EC1 and a reactor R1 connected through a conduit allowing controlled passage of gas, and D2 comprises an evaporator/condenser EC2 and a reactor R2 connected through a conduit allowing controlled passage of gas; • EC1 contains a gas G1 and R1 contains a sorbent S1 capable of forming a reversible physico-chemical process with G1, and EC2 contains a gas G2 and R2 contains a sorbent S2 capable of forming a reversible physico-chemical process with G2; • the applied gases and sorbents are selected so that, at a given pressure, the equilibrium temperatures of the thermochemcal phenomena in the reactors and the evaporators/condensers are such that T ≤ T < T < T; • the dipoles D1 and D2 are provided with means allowing their coupling with each other via a thermal route when G1 and G2 are different and via a massive route when G1 and G2 are identical; • the thermochemical phenomena in the evaporators/condensers are selected from the phase transition L/G of ammonia (NH 3), the phase transition of methylamine (NH 2 CH 3) and the phase transition of H 2 O; • the thermochemical phenomena in the reactors are selected from reversible chemical sorptions of NH 3 by CaCl 2, by SrCl 2, or by BaCl 2, or of NH 2 CH 3 by CaCl 2, the adsorption of water by zeolite or a silica gel, the adsorption of methanol or ammonia in active coal, and the adsorption of NH 3 in a liquid solution of ammonia (NH 3, H 2 O). • the thermochemical phenomena in the dipole D2 are such that this dipole may produce refrigeration at Tf with a heat sink at room temperature To; • the thermochemical phenomena in the dipole D1 are such that this dipole may be regenerated from the heat source Th and a heat sink at temperature To; • D1 comprises an evaporator/condenser EC1 and a reactor R1 connected through a conduit allowing controlled passage of gas, and D2 comprises an evaporator/condenser EC2 and a reactor R2 connected through a conduit allowing controlled passage of gas; • EC1 contains a gas G1 and R1 contains a sorbent S1 capable of forming a reversible physico-chemical process with G1, and EC2 contains a gas G2 and R2 contains a sorbent S2 capable of forming a reversible physico-chemical process with G2; • the applied gases and sorbents are selected so that, at a given pressure, the equilibrium temperatures of the thermochemcal phenomena in the reactors and the evaporators/condensers are such that T ≤ T < T < T; • the dipoles D1 and D2 are provided with means allowing their coupling with each other via a thermal route when G1 and G2 are different and via a massive route when G1 and G2 are identical; • the thermochemical phenomena in the evaporators/condensers are selected from the phase transition L/G of ammonia (NH 3), the phase transition of methylamine (NH 2 CH 3) and the phase transition of H 2 O; • the thermochemical phenomena in the reactors are selected from reversible chemical sorptions of NH 3 by CaCl 2, by SrCl 2, or by BaCl 2, or of NH 2 CH 3 by CaCl 2, the adsorption of water by zeolite or a silica gel, the adsorption of methanol or ammonia in active coal, and the adsorption of NH 3 in a liquid solution of ammonia (NH 3, H 2 O).