An azeotropic or azeotrope-like composition consists of: 1-99 wt. % 1, 1, 2, 2, 3-pentafluoropropane and 1-99 wt. % 1, 1, 1, 2, 3-pentafluoropropane; 1-36 wt. % 1, 1, 2, 2, 3-pentafluoropropane and 64-99 wt. % 1, 1, 1-trifluoropropane; 1-55 wt. % 1, 1, 2, 2, 3-pentafluoropropane and 45-99 wt. % 2, 2-difluoropropane; 1-99 wt. % 1, 1, 2, 2, 3-pentafluoropropane and 1-99 wt. % 1, 2-difluoropropane; 1-73 wt. % 1, 1, 2, 2, 3-pentafluoropropane and 27-99 wt. % butane; 1-55 wt. % 1, 1, 2, 2, 3-pentafluoropropane and 45-99 wt. % and cyclopropane; 1-65 wt. % 1, 1, 2, 2, 3-pentafluoropropane and 35-99 wt. % isobutane; 1-57 wt. % 1, 1, 1, 2, 2, 3-pentafluoropropane and 43-99 wt. % propane; 70-99.5 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 0.5-30 wt. % 1, 1, 1, 2, 3-pentafluoropropane; 74-99 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 1-26 wt. % 1, 2, 2, 3-tetrafluoropropane; 75-99 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 1-25 wt. % 1, 2-difluoropropane; 1-99 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 1-99 wt. % 2-fluoropropane; 59-99 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 1-41 wt. % 1-fluoropropane; 59-99 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 1-41 wt. % butane; 1-90 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 10-99 wt. % cyclopropane; 1-89 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 11-99 wt. % dimethyl ether; 40-99 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 1-60 wt. % isobutane; 1-76 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 24-99 wt. % propane; 1-69 wt. % 1, 1, 1, 2, 2-pentafluoropropane and 31-99 wt. % propylene; 1-45 wt. % 1, 1, 2, 3, 3-pentafluoropropane and 55-99 wt. % 2,2-difluoropropane; 1-55 wt. % 1, 1, 2, 3, 3-pentafluoropropane and 45-99 wt. % 1,2-difluoropropane; 1-54 wt. % 1, 1, 2, 3, 3-pentafluoropropane and 46-99 wt. % 1, 1, 1, 4, 4, 4-hexafluorobutane; 1-56 wt. % 1, 1, 2, 3, 3-pentafluoropropane and 44-99 wt. % 1, 1, 1, 2, 3, 4, 4, 5, 5, 5-decafluoropentane; 1-65 wt. % 1, 1, 2, 3,3-pentafluoropropane and 35-99 wt. % butane; 1-54 wt. % 1, 1, 2, 3, 3-pentafluoropropane and 46-99 wt. % cyclopropane; 1-62 wt. % 1, 1, 2, 3, 3-pentafluoropropane and 38-99 wt. % isobutane; 1-57 wt. % 1, 1, 2, 3, 3-pentafluoropropane and 43-99 wt. % propane; 1-99 wt. % 1, 1, 1, 2, 3-pentafluoropropane and 1-99 wt. % 1, 2, 2-trifluoropropane; 1-43 wt. % 1, 1, 1, 2, 3 - pentafluoropropane and 57-99 wt. % 1, 1, 1-trifluoropropane; 11-99 wt. % 1, 1, 1, 2, 3-pentafluoropropane and 1-89 wt. % 1, 1, 1, 4, 4, 4-hexafluorobutane; 21-71 wt. % and 29-79 wt. % butane; 1-56 wt. % 1, 1, 1, 2, 3-pentafluoropropane and 44-99 wt. % cyclopropane; 1-66 wt. % 1, 1, 1, 2, 3-pentafluoropropane and 34-99 wt. % isobutane; 1-57 wt. % 1, 1, 1, 2, 3-pentafluoropropane and 43-99 wt. % propane; 1-78 wt. % 1, 1, 1, 3, 3-pentafluoropropane and 22-99 wt. % butane; 1-60 wt. % 1, 1, 1, 3, 3-pentafluoropropane and 40-99 wt. % isobutane; or 58-99 wt. % 1, 1, 1, 3, 3-pentafluoropropane and 1-42 wt. % pentane. Processes for heating and refrigeration using the binary compositions are also claimed.    USE -   The compositions are used for heating and cooling objects, as blowing agents in the production of polymer foams and for cleaning surfaces (all claimed). The compositions are also used as aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, power cycle working fluids, polymerisation media, particulate removal fluids, carrier fluids, buffing abrasive agents or displacement drying agents.    ADVANTAGE -   The compositions have low ozone depletion potential. As the compositions are azeotrope (like), they do not tend to fractionate on evaporation, which could lead to a changed composition that is flammable and which may have less desirable solvency properties.