The Sail Switch activates an electronic air
cleaner, a humidifier, or other equipment in
response to airflow j?om the system fan. The
S688A is rnountedin the return air duct where the
sail will be in the direct path of an unrestricted
Simplified installations with mukispeed fans, in-
accessible air handlers, fan motors with voltage or
phase different from controlled equipment; elimi-
nated wiring to system fan.
Removable spring counterbalances sail to allow
mounting in either vertical (up or down) or hori-
zontal air flow.
Top and bottom conduit knockouts for wiring
Low air velocity switch operation—makes at
250 fpm and breaks at 75 fpm.