The Spacing of Ceiling Fans for Human Comfort in Warm Temperature Conditions

Abstract

Airspeed tests of a commercially popular 52 in. ceiling fan operating at a low speed of 155 fpm provided sufficient airspeed for comfort to 82F in an average floor area of 97.2 ft^2 beneath the fan. When operating at maximum speed, the average floor area increased to 151.0 ft^2. At 85F, the average floor areas for the low speed and maximum speed tests were 31.8 ft^2 and 55.6 ft^2 respectively. The maximum on-center spacing recommended for the tested ceiling fan mounted at 8.5 ft. above the floor, operating at maximum speed, and providing comfort at a room temperature of 82F is 14 ft.; and at a temperature of 85F, it is 9 ft. Future ceiling fans should be designed to create a both a larger main air plume and a larger comfort zone. The ceiling fan provided relatively high air-speeds throughout the largest floor area in the zone from the floor to the 24 in. height. Since ceiling fans create higher airspeeds near the floor, they should be used cautiously when rooms are comfortably conditioned during all seasons and have children playing in the room or adults sitting on the floor of the room.