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  • Sense low flow independent of pressure or temperature.
  • Turn off power or gas to heater to prevent meltdown.
  • Automatic reset – ready to go as soon as flow is re-established.
  • For direct control of pump motors, heaters, solenoid valves, etc.
  • UL component recognized (E85349)


  • SPDT, 1/2 hp, 15 AMP switching capacity @ 115 or 230 VAC standard, 25 amp, 1 HP/120 VAC: 2 HP/230 VAC on special order.
  • Wide operating range – 5 to 80 GPM, Pipe Size 1 1/2″ or 2″.
  • Quick, easy, horizontal, vertical or inverted installation in any plastic tee with a 1″ NPT side port.

Electrical Switch Characteristics

  • SPDT UL and CSA listed
  • 15 amp, 1/2 HP @ 125 or 250 VAC
  • 1/2 amp @ 125 VDC, 1/4 amp @ 250 VDC
  • 5 amp @ 125 VAC (Tungsten lamp load)
  • 10,000,000 operations median
  • FACTORY SET SWITCH POINT (1 1/2″ PIPE):Increasing flow 5-20 GPM. Decreasing flow 3-13 GPM.Consult factory for special set points
  • DIFFERENTIAL PRESSURE DROP:1 1/2″ to 2″ pipe – less than 1.0 psi
  • WORKING LINE PRESSURE: 50 psig max @ 180°F max
  • MAXIMUM TEMPERATURE:180°F continuous
  • WETTED SURFACES: Noryl, 316 and 301 stainless steel, Viton
  • WEIGHT: 1/4 lb.

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