Model AFS-145 Air Pressure Sensing Switch is a general purpose proving switch designed for package burner, furnace, fuel-burning equipment, HVAC and other Energy Management applications. It can be used to sense positive, negative, or differential air pressure. The AFS-145 has a field adjustable set point range of 0.05″ wc to 12.0″ wc. The screw terminals are protected by an enclosure that accepts 1/2″ conduit. This switch has an SPDT contact arrangement. The two ⅛”–27 NPT female sample line connectors located on either side of the silicone diaphragm accept ⅛” pipe.

• Mounting Position: Mount with the diaphragm in any vertical plane.
• Set Point Range: 0.05 ± 0.02" w.c. to 12.0"w.c.
• Field Adjustable “Operate Range”: 0.07"w.c. to 12.0" w.c.
• Field Adjustable “Release Range”: 0.04"w.c. to 11.2" w.c.
• Approximate Switching Differential: Progressive, increasing from 0.02 ± 0.01"w.c. at minimum set point to approximately 0.8" w.c. at maximum set point.
• Measured Media: Air, or combustion by-products that will not degrade silicone.
• Maximum Pressure: 1/2" psi (0.03 bar).
• Operating Temperature Range: -40F to 180F (-40 to 82C).
• Life: 100,000 cycles minimum at 1/2 psi maximum pressure each cycle and at maximum rated electrical load.
• Electrical Rating: 300 VA pilot duty at 115 to 277 VAC, 15 amps noninductive to 277 VAC, 60 Hz.
• Contact Arrangement: SPDT
• Electrical Connections: Screw-type terminals with cup washers.
• Conduit Opening: 7/8" diameter opening accepts 1/2"conduit.
• Sample Line Connectors: 1/8" - 27 NPT female connectors (2).
• Sample Line Connections: Connectors will accept ¼" OD rigid or semi-rigid tubing.
• Approvals: UL, FM, CSA.
• Shipping Weight: 1.2 lbs.
• Accessories:
  • P/N 18311 Slip-on ¼" OD Tubing Adapter, suitable for slipping on flexible plastic tubing.
  • Sample line probes.
  • Orifice plugs (pulsation dampers).