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Part of the 174A Series

Ordering Code: 0274426

UPC: 098268013030

Lead Free: NO

3/4 In Bronze Boiler Pressure Relief Valve, 33 psi, Female Threaded Connections

This 3/4 inch 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 pressure relief is set at 33 psi (228 kPa) with corresponding high pressure ratings up to 695,000 BTU/hr.695,000 BTU/hr.

Product Features

  • Water can't be trapped and sediment can't foul seat
  • Water seal of high temperature resisting material isolates spring working parts from water during relief
  • Non mechanical seat-to-disc alignment will not stick or freeze
  • Bronze body safety relief valves for pressure protection only of all types of hot water heating boiler equipment
Body Material Bronze
Brand Name Watts
Inlet Connection Size 3/4 IN
Inlet Connection Type Female Threaded
Inlet Thread Type NPT
Lead Free NO
Maximum Temperature-Fahrenheit 250
Model Number 174A-033
Outlet Connection Size 3/4 IN
Outlet Connection Type Female Threaded
Outlet Thread Type NPT
Part Number 0274426
Pressure Range 30 to 150 PSI
Pressure Relief Setting-PSI 33
Pressure Steam Discharge Capacity 695000 BTU per hour at 33 PSI
Protection Type Pressure
Series 174A