Abstarct: One of the subjects in solar water heater design is considering distribution of hot water consumption during the day. For example, each of the household, commercial, office, school, and industrial consumptions have a particular distribution of hot water consumption named pattern in this article. In solar computation principles, the effect of longitude, latitude, and altitude on collector angle has been clearly presented. However, the effect of consumption patterns especially on the collector orientation has been rarely investigated. The aim of the current study is to survey the effect of various consumption patterns on the collector’s orientation and tilt angle and so calculation of related energy saving. So, five common patterns including office building, commercial building, afternoon and morning shift high school and a 15-unit apartment have been studied and optimal surface azimuth angle and tilt angle determined. It has been observed that 11 to 14 % energy saving can be archived by selecting the optimal angles with respect to hot water consumption pattern in comparison to a state that collectors are orientated for maximum reception of solar energy. Also effect of solar fraction, storage volume and amount of hot water consumption are studied and discussed. With comparison to direct and indirect solar water heating systems in simultaneity optimization of design parameters including collectors' area, storage volume, tilt angles, and collectors' orientation has been delineate that in indirect systems, collectors' orientation with respect to type of consumption because of variations of storage temperature, have more variations than maximum energy absorption and reach to 17 centigrade.