The Danfoss 061H4000 is an FQS series flow switch designed for dependable liquid flow detection in HVAC, hydronic, and refrigeration piping systems. Featuring a 1-inch pipe connection and a Single-Pole Double-Throw (SPDT) switching configuration, this flow switch provides versatile normally-open or normally-closed circuit control to protect pumps, boilers, chillers, and other fluid-handling equipment from dry-run or no-flow conditions.
Key Features
- FQS series flow switch from Danfoss — a trusted name in HVAC and refrigeration controls
- 1″ pipe size connection for straightforward inline installation
- SPDT (Single-Pole Double-Throw) switching action for flexible NO or NC circuit wiring
- Designed to detect flow presence or absence, protecting downstream equipment
- Suitable for hydronic heating and cooling systems, chiller plants, and process piping
- Compact, robust construction for long service life in commercial and industrial applications
Applications
- Boiler and chiller flow proving circuits
- Hydronic heating and cooling system protection
- Pump protection and interlock control
- Commercial HVAC water-side equipment
- Refrigeration and process fluid systems
Product Specifications
- Brand: Danfoss
- SKU / Part Number: 061H4000
- Series: FQS
- Pipe Size: 1″
- Switch Type: SPDT (Single-Pole Double-Throw)
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