The performance of a solar driven CH4O-H2O combined ejector- absorption unit, operating in conjunction with intermediate temperature solar collectors in Athens, is predicted along the five months (May-September) in case of the unit working as heat pump in an industrial area. The operation of the unit and the related thermodynamics are simulated by suitable computer codes and the required local climatological data are determined by statistical processings over a considerable number of years. It is found that the heat gain factor varies in the range from 2.1330 to 2.4481 for the above period of time. The maximum HGF of about 2.4481 is obtained in July at 14.25 hrs with corresponding specific heat gain power 915 W/m(2) The maximum Q(gain) of about 1086 W/m(2) is obtained in June at 12.54 hrs with corresponding HGF 2.3572. Also the maximum value of HGF was estimated by correlation of three temperatures: generator temperature (85.0 degreesC-97.2 degreesC), condenser temperature (43.3 degreesC-47.6 degreesC) and evaporator temperature (12.6 degreesC-25.4 degreesC).