IOM
Model: 43T Pressure Relief Valve
PAGE 4 OF 10
Figure 1: Installation Drawing
4.
Operation
The Pressure-Relief Pilot Valve (#1, fig.2) senses inlet pressure and modulates the control chamber causing the
main valve to throttle, thus sustaining constant inlet pressure. When the inlet pressure rises above the setting,
the pilot valve opens pressure in the control-chamber decreases and the main valve modulates open to relieve
inlet pressure and sustain pilot valve setting.
The pressure-relief pilot valve is equipped with an adjusting screw (#4, fig.2) to preset the desired inlet pressure.
Figure 2A: Operation Drawing for Size 3, 4 and 6"
