Opening Pressure Test
- Open tester shut off valve to pressure gauge 1/4 turn. Slowly depress tester lever and observe pressure gauge. Note pressure at which needle stops, indicating pressure increase (nozzle does not chatter) or at which pressure drops substantially (nozzle chatters).
- Maximum pressure is opening pressure. Lowest acceptable pressure is 1500 psi (105 kg/cm2 ). Replace any nozzle which does not meet lowest acceptable pressure. Release tester pressure.