Resideo by Honeywell S688A1007/B SPDT Sail Switch with 5" Wide Sail for HVAC Air Flow Detection

The Resideo S688A1007/B Sail Switch activates an electronic air cleaner, a humidifier, or other equipment in response to airflow from the system fan. The S688A is mounted in the return air duct where the sail will be in the direct path of an unrestricted air stream. This air flow switch is ideal for HVAC applications where reliable airflow detection is critical for activating auxiliary equipment.

Key Features:

• Polyester film sail mounted on a micro switch snap switch for positive feedback and reliable operation
• Removable spring counterbalances sail to allow mounting in either vertical (up or down) or horizontal air flow
• Low air velocity switch operation makes at 250 fpm and breaks at 75 fpm
• Top and bottom conduit knockouts for wiring convenience
• Simplified installations with multi-speed fans, inaccessible air handlers, fan motors with voltage or phase different from controlled equipment; eliminated wiring to system fan
• SPDT (Single Pole Double Throw) snap-acting switch for versatile wiring configurations

Technical Specifications:

• Dimensions: 2 15/16" H x 3 3/4" W x 2" D
• Sail dimensions: 5" wide (max), 26.2 sq. in. of area
• Mounting: Switch mounts on return air duct with two sheet metal screws
• Sail is inserted into duct through 1.5" H x 2.3" W hole
• Maximum ambient temperature: 125°F (52°C) at switches; 170°F (77°C) at sail
• UL Listed: File No. E4436, Guide No. XAPX
• Includes adhesive backed mounting template

The S688A1007/B provides dependable airflow detection for residential and light commercial HVAC systems, ensuring auxiliary equipment operates only when the system fan is running. Its low velocity operation and versatile mounting options make it suitable for a wide range of ductwork configurations.