







WFSR-F | Potter Pressure-Activated Waterflow Alarm Switch with Pneumatic Retard
- Regular price
- $1,051.00
- Sale price
- $1,051.00
- Regular price
-
$0.00
Couldn't load pickup availability
Do you need help?

Product Description P/N: WFSR-F
Description
The Potter WFSR-F is a pressure-activated waterflow alarm switch with pneumatic retard designed for automatic sprinkler systems. It detects rising water pressure associated with sprinkler activation and initiates an alarm signal for system notification.
Technical Specifications
Condition | New/Never Used Surplus |
Brand | Potter |
Category | Fire Sprinkler Equipment |
Part Number | WFSR-F |
Subcategory | Waterflow Alarm Switch |
Product Type | Pressure-activated waterflow switch |
Activation Type | Pressure rise, 5–8 PSI (0.35–0.55 BAR) |
Pressure Connection | ½” Male NPT |
System Pressure | 175 PSI (12.1 BAR) maximum |
Pressure Adjustment | Factory set, adjustable range available |
Retard Type | Pneumatic retard mechanism |
Electrical Contacts | Two SPDT (Form C) |
Contact Ratings | 15A @ 125/250 VAC, 2A @ 30 VDC (resistive) |
Enclosure Rating | NEMA 4 / IP54 weather-resistant |
Housing Material | Die-cast aluminum base, composite cover |
Environmental Range | 40°F to 120°F (4.5°C to 49°C) |
Conduit Entrances | Two knockouts for ½” conduit |
Standards Compliance | NFPA 13, NFPA 13D, NFPA 13R, NFPA 72 |
Mounting | Vertical or horizontal, threaded connection |
Weight | 1.5 lbs (0.68 kg) |
Production Status | Discontinued (replaced by Potter VSR-5) |
Information About WFSR-F
The WFSR-F is part of Potter’s WFSR Series of pressure-type waterflow switches, built to monitor wet sprinkler piping in compliance with NFPA standards. This model is factory-set to activate between 5 and 8 PSI (0.35–0.55 BAR) on rising pressure and features a pneumatic retard mechanism to prevent false alarms due to pressure fluctuations. Housed in a NEMA 4/IP54 weather-resistant enclosure, it is suitable for both indoor and outdoor installations. The unit includes dual SPDT contacts rated for up to 15 amps at 250 VAC and is compatible with automatic sprinkler, NFPA-13D, and NFPA-13R residential systems. The WFSR-F has been discontinued by the manufacturer and superseded by the VSR-5 model.
Key Features:
- Pressure-Activated Detection: Triggers alarm upon rising system pressure (5–8 PSI).
- Pneumatic Retard: Reduces false alarms caused by transient pressure surges.
- Dual SPDT Contacts: Two Form C contacts rated 15A at 125/250 VAC, 2A at 30VDC.
- Weather-Resistant Housing: NEMA 4/IP54-rated enclosure for indoor/outdoor use.
- Durable Construction: Die-cast aluminum base with UV/flame-resistant composite cover.
- NFPA-Compliant: Meets NFPA 13, 13D, 13R, and 72 requirements for sprinkler monitoring.
- Pressure Connection: ½” Male NPT fitting for straightforward installation.
- Factory Adjusted: Calibrated for reliable performance under 175 PSI system pressure.
The WFSR-F delivers the reliability and precision required for sprinkler system waterflow detection, though it has been discontinued and replaced by the Potter VSR-5.
Description
The Potter WFSR-F is a pressure-activated waterflow alarm switch with pneumatic retard designed for automatic sprinkler systems. It detects rising water pressure associated with sprinkler activation and initiates an alarm signal for system notification.
Technical Specifications
Condition | New/Never Used Surplus |
Brand | Potter |
Category | Fire Sprinkler Equipment |
Part Number | WFSR-F |
Subcategory | Waterflow Alarm Switch |
Product Type | Pressure-activated waterflow switch |
Activation Type | Pressure rise, 5–8 PSI (0.35–0.55 BAR) |
Pressure Connection | ½” Male NPT |
System Pressure | 175 PSI (12.1 BAR) maximum |
Pressure Adjustment | Factory set, adjustable range available |
Retard Type | Pneumatic retard mechanism |
Electrical Contacts | Two SPDT (Form C) |
Contact Ratings | 15A @ 125/250 VAC, 2A @ 30 VDC (resistive) |
Enclosure Rating | NEMA 4 / IP54 weather-resistant |
Housing Material | Die-cast aluminum base, composite cover |
Environmental Range | 40°F to 120°F (4.5°C to 49°C) |
Conduit Entrances | Two knockouts for ½” conduit |
Standards Compliance | NFPA 13, NFPA 13D, NFPA 13R, NFPA 72 |
Mounting | Vertical or horizontal, threaded connection |
Weight | 1.5 lbs (0.68 kg) |
Production Status | Discontinued (replaced by Potter VSR-5) |
Information About WFSR-F
The WFSR-F is part of Potter’s WFSR Series of pressure-type waterflow switches, built to monitor wet sprinkler piping in compliance with NFPA standards. This model is factory-set to activate between 5 and 8 PSI (0.35–0.55 BAR) on rising pressure and features a pneumatic retard mechanism to prevent false alarms due to pressure fluctuations. Housed in a NEMA 4/IP54 weather-resistant enclosure, it is suitable for both indoor and outdoor installations. The unit includes dual SPDT contacts rated for up to 15 amps at 250 VAC and is compatible with automatic sprinkler, NFPA-13D, and NFPA-13R residential systems. The WFSR-F has been discontinued by the manufacturer and superseded by the VSR-5 model.
Key Features:
- Pressure-Activated Detection: Triggers alarm upon rising system pressure (5–8 PSI).
- Pneumatic Retard: Reduces false alarms caused by transient pressure surges.
- Dual SPDT Contacts: Two Form C contacts rated 15A at 125/250 VAC, 2A at 30VDC.
- Weather-Resistant Housing: NEMA 4/IP54-rated enclosure for indoor/outdoor use.
- Durable Construction: Die-cast aluminum base with UV/flame-resistant composite cover.
- NFPA-Compliant: Meets NFPA 13, 13D, 13R, and 72 requirements for sprinkler monitoring.
- Pressure Connection: ½” Male NPT fitting for straightforward installation.
- Factory Adjusted: Calibrated for reliable performance under 175 PSI system pressure.
The WFSR-F delivers the reliability and precision required for sprinkler system waterflow detection, though it has been discontinued and replaced by the Potter VSR-5.



