Xylem FS4-3 General Purpose Liquid Flow Switch 1" NPT SPDT

The Xylem FS4-3 (McDonnell & Miller 114400) is a general purpose liquid flow switch designed for reliable flow monitoring in boiler systems, HVAC applications, and industrial processes. This versatile flow switch features a 1-inch NPT connection and includes multiple stainless steel paddles for flexible installation in various pipe sizes.

Key Features:

• Flow rate range: 6 to 166 GPM for versatile application compatibility
• Maximum pressure rating: 160 PSI for dependable performance
• Temperature range: 32°F to 300°F for diverse operating conditions
• Dual voltage operation: 120/240 VAC, 50/60 Hz with 125 VA power consumption
• SPDT (Single Pole Double Throw) switch for flexible circuit control
• NEMA 1 enclosure provides protection in indoor environments
• Includes four stainless steel paddles: 1", 2", 3", and 6" lengths
• Brass and stainless steel body construction for corrosion resistance
• Maximum flow velocity: 10 feet per second
• Sensitivity adjusting screw allows easy flow rate calibration
• Dual electrical knockouts for convenient wiring from either end

The FS4-3 features a durable sealed monel bellows design and adjustable sensitivity settings to accommodate specific flow monitoring requirements. Compact dimensions (8-7/16" H x 3-3/8" W x 3" D) allow for easy installation in tight spaces. Ideal for use in steam and hot water boiler systems, cooling water circuits, and general liquid flow detection applications.