Operating distribution networks in southern region of Iran located in northern coasts of Persian Gulf and Oman Sea requires special conditions. Environmental conditions like high temperature and humidity, Sunlight severity, very low raining, Obstacles in the air in addition with conditions like high energy consumption per capital, fast growth of energy demand because of new air conditioning systems and immigration of people to this region and converting this region to the largest industrial zone of Iran, all caused a very fast age reduction in distribution networks installed, so that the rate of aging has been estimated up to 40%. Considering above mentioned conditions and our experts' high load of work for operating and maintaining the old installations in addition with their efforts for avoiding the black-outs, Objectives of the Hormozgan Electric Power Distribution Co for reducing the black-outs caused rescheduling old preventive maintenance plans. This paper is a review of Hormozgan Electric Power Distribution Company's experiences using thermographs for preventive maintenance and inspection in Hormozgan region. In this project, 151 middle voltage feeders in 5,700 Km grid were inspected and 2,200 lose connections were discovered. Fixing these loose connections resulted reducing 10.5 MW power losses and reduce the costs of operation up to 39 million USD during the year 2009.