Description
Overview
The Xylem-McDonnell & Miller FS4-3RP-T is a general purpose liquid flow switch engineered for reliable flow detection in a wide range of hydronic and liquid piping systems. Featuring a 1″ NPT connection and a single-pole, double-throw (SPDT) switching action, this unit delivers dependable on/off control in response to liquid flow changes — making it an ideal choice for boiler protection, pump proving, chiller circuits, and other HVAC/R hydronic applications.
Key Features
- 1″ NPT pipe connection for straightforward installation into standard piping
- SPDT (Single-Pole, Double-Throw) switch for versatile normally-open or normally-closed circuit control
- Rated for up to 160 PSI maximum working pressure
- Includes both 1″ and 6″ stainless steel paddles to accommodate a variety of pipe sizes and flow conditions
- Built-in test button allows technicians to manually verify switch operation without requiring flow
- General purpose design suitable for water, glycol solutions, and other compatible liquids
- Durable construction for long-term reliability in demanding HVAC and hydronic environments
Paddle Options
The FS4-3RP-T ships with two stainless steel paddle sizes — a 1″ paddle and a 6″ paddle — providing installation flexibility across different pipe diameters and flow velocities. Stainless steel construction resists corrosion and ensures long service life in wet system environments.
Test Button Functionality
The integrated test button is a valuable service feature that allows field technicians to simulate switch actuation and confirm proper wiring and control circuit operation without the need to create or interrupt actual liquid flow. This simplifies commissioning, troubleshooting, and routine maintenance.
Typical Applications
- Hydronic heating and cooling systems
- Boiler low-water and pump-proving protection
- Chiller and cooling tower circuits
- Pump flow verification
- General liquid flow detection and control
Specifications
- Brand: Xylem-McDonnell & Miller
- Part Number: FS4-3RP-T (114639)
- Connection Size: 1″ NPT
- Switch Type: SPDT (Single-Pole, Double-Throw)
- Maximum Working Pressure: 160 PSI
- Paddle Material: Stainless Steel
- Included Paddles: 1″ and 6″
- Test Button: Yes
Reviews
There are no reviews yet.