Ceiling fan speed controls for comfort in warm environments.

Human thermal comfort in warm conditions can often be improved inexpensively by increased air movement. Two automatic ceiling fan systems are described that regulate air speed to maintain comfort in changing conditions. One system is based on the ASHRAE comfort standard and the other uses the PMV comfort model. In comfort tests at 29°C and 50% RH both automatic systems provided the same level of comfort at steady state conditions as manual control. However the automatic systems were faster in bringing the subjects to comfort. The comfort performance of the two automatic systems were also compared during a temperature down drift from 29°C to 25°C.