In the given work there is shown the methodology of simulating the experimental model of solar water heating unit. Using theoretical and experimental outcomes, also, obtained rated values of transmittance medium in solar collector, there has been carried out predictive analysis of solar irradiation flow density, ambient temperature and temperature in the accumulator tank. Estimated and experimental daily characteristics of both systems have efficient accuracy of 7%, which proves reliability of constructive formulae and engineering model. As well, there has been computed the unit capacity factor, plants’ production growth constitutes from 0.5 to 0.85%. Computed the coefficient, which depends on heat flow and solar collector’s surface, as well on convective heat exchange between solar irradiation and solar collector’s surface. Experimentally executed computation of solar water heating unit’s performance, which is fulfilled in compliance with hourly sums of direct and scattered irradiation and ambient temperature