In many parts of the world and during a good part of the year, comfort can be attained or improved with minimal energy by just opening or adjusting the window. The air flow through the window opening can reduce the temperature and humidity and increase air motion in the space, all leading to reduced warm discomfort. This approach to energy conservation can be also be done with a system developed and tested in this paper, comparison tests with the window automatically controlled and with the window manually adjusted by the occupant shows both were equally successful in providing comfort.