(US5736062-A)      Quasi-azeotropic mixts. comprise: (1) 20-59 wt.% CF3-CHF2 (R-125); 40-75 wt.% CHClF2 (R-22); and 1-10 wt.% cyclopropane (RC-270); (2) 20-42 wt.% CF3-CH3 (R143a); 57-75 wt.% R-22; and 1-5 wt.% propane (R-290); (3) 5-30 wt.% CH2F2 (R-32); 68-90 wt.% R-22; and 1-5 wt.% R-290; (4) 49-60 wt.% R-125; 35-49 wt.% R-143a; and 1-5 wt.% RC-270 or R-290; (5) 5-10 wt.% R-143a; (6) 20-50 wt.% R-125; 5-20 wt.% R-143a; 1-5 wt.% R-290; and 40-60 wt.% R-22; (7) 2-8 wt.% R-32; 88-97 wt.% CF3-CH2F (R-134a); and 1-5 wt.% dimethylether (DME); (8) 3-10 wt.% R-143a; 85-96 wt.% R134a; and 1-5 wt.% DME; or (9) 5-20 wt.% R-125; 75-90 wt.% R-134a; and 1-5 wt.% DME.    USE -   The mixts. are useful as refrigerating fluids (claimed), esp. in circuits working according to the Rankine cycle.    ADVANTAGE -   The quasi-azeotropic mixts. are non-flammable and are characterised by vapour pressure curves such as to make them particularly suitable as substitutes for refrigerants R-12 or R-502. The environmental impact of the mixts. w.r.t. ozone depletion and global warming is very low or null.    (EP638623-B1)      Quasi-azeotropic mixts. comprise: (1) 20-59 wt.% CF3-CHF2 (R-125); 40-75 wt.% CHClF2 (R-22); and 1-10 wt.% cyclopropane (RC-270); (2) 20-42 wt.% CF3-CH3 (R143a); 57-75 wt.% R-22; and 1-5 wt.% propane (R-290); (3) 5-30 wt.% CH2F2 (R-32); 68-90 wt.% R-22; and 1-5 wt.% R-290; (4) 49-60 wt.% R-125; 35-49 wt.% R-143a; and 1-5 wt.% RC-270 or R-290; (5) 5-10 wt.% R-143a; (6) 20-50 wt.% R-125; 5-20 wt.% R-143a; 1-5 wt.% R-290; and 40-60 wt.% R-22; (7) 2-8 wt.% R-32; 88-97 wt.% CF3-CH2F (R-134a); and 1-5 wt.% dimethylether (DME); (8) 3-10 wt.% R-143a; 85-96 wt.% R134a; and 1-5 wt.% DME; or (9) 5-20 wt.% R-125; 75-90 wt.% R-134a; and 1-5 wt.% DME.    USE -   The mixts. are useful as refrigerating fluids (claimed), esp. in circuits working according to the Rankine cycle.    ADVANTAGE -   The quasi-azeotropic mixts. are non-flammable and are characterised by vapour pressure curves such as to make them particularly suitable as substitutes for refrigerants R-12 or R-502. The environmental impact of the mixts. w.r.t. ozone depletion and global warming is very low or null.