Experiments on performance of evacuated tube collector were conducted in outdoor conditions to compare performance of evacuated tube collector by using water and Seriola 1510 thermal oil as working medium. The collector was made up of 10 heat pipes, each 1,700 mm long and 70 mm outside diameter. Three tanks, each with 100 l capacity; include collector tank, hot storage tank and cold storage tank were used. TC-08 data logger and Eppley 8–48 pyranometer were used. Measurements were taken between 0630 to 1830 at an interval of 1 min. Thermocouple inserted to the evaporator for heat pipe on outlet side attained maximum temperature of 174 °C while maximum temperature achieved in the condenser for heat pipe on outlet side was 148 °C. With maximum solar irradiance of about 664 W/m2 during the days, highest temperature for water heating was recorded to be 70 °C and for the case of thermal oil, temperature soared to 114 °C. Maximum collector efficiency was around 69% for water heating, and 55% for oil heating. However, oil lost about 2.9 MJ after 12 h while water lost more than 5.4 MJ at similar period of time. Oil heating provides promising results for low grade domestic heating applications including adsorption refrigeration.