Watts 3/4" x 3/4" Bronze Pressure Relief Valve, FPT x FPT, 30 PSI

WA174AI30 MFG #: 174A-3/4-30
  • Brand: WATTS®
This boiler pressure relief valve is used in hot water heating and domestic supply boiler applications to protect against excessive pressures on all types of hot water heating supply boiler equipment. It consists of a bronze body construction with NPT threaded female inlet and NPT threaded female outlet (drain) connections, non-metallic disc-to-metal seating, stainless steel spring, and test lever. It resists corrosive water conditions, sticking and freezing, and prevents water and sediment from being trapped in the seat. It is designed for emergency safety relief, not as an operating control. The standard pressure setting is 30psi (206.9 kPa), Pressure Range: In 5psi (34.5 kPa) increments from 30 to 150psi (2 to 10 bar) with corresponding high ratings from 650,000 to 14,370,000 BTU/hr.
  • Features
  • Features and More
  • Seat located above drain; water can't be trapped and sediment can't foul seat
  • Non-mechanical seat-to-disc alignment will not stick or freeze
  • Water seal of high temperature resisting material isolates spring working parts from water during relief
  • Nonmetallic disc-to-metal seating
  • The discharge line must be the same size as the valve outlet, and must pitch downward from the valve to a safe place for disposal
  • Valve lever must be tripped at least once a year to ensure that waterways are clear, This device is designed for emergency safety relief and shall not be used as an operating control
  • ASME Section IV, MIL-V-18634B


  • Non-Mechanical Seat to Disc Alignment will Not Stick or Freeze
  • Water Seal of High Temperature Resisting Material Isolates Spring Working Parts from Water During Relief
  • Seat Located above Drain
  • It Resists Corrosive Water Conditions, Sticking and Freezing and Prevents Water and Sediment from Being Trapped in the Seat
  • It is Designed for Emergency Safety Relief and Shall Not be Used as an Operating Control


    Non-Metallic Disc to Metal Seating, Test Lever