TM 10-4610-240-10
TM 08580C-10/1
T.O. 40W4-13-21
2-8. SAFETY DEVICES.
The ROWPU has automatic safety devices: the high pressure relief valve, the high pressure switch, and the rupture disc
assembly.
a. High Pressure Relief Valve. The high pressure relief valve is located just behind the VENT VESSEL VALVE. If
R.O. pressure goes above 1 100psi, this valve opens automatically and discharges water through a pipe at the back of
the ROWPU. If this valve activates (indicated by sudden pressure loss), immediately press the PUSH EMERGENCY
STOP switch. Open REGULATE PRODUCT FLOW VALVE after unit is shut down. When the pressure drops below 1
100 psi, the valve will close automatically.
FIGURE 2-47. HIGH PRESSURE RELIEF VALVE, HIGH PRESSURE SWITCH AND RUPTURE DISC
CAUTION
If the valve does not close automatically, notify unit maintenance and do not try to restart the
ROWPU.
After the high pressure relief valve closes, clean the R.O. elements (see paragraph 2-12) and start the ROWPU in the
b. High Pressure Switch. The high pressure switch is mounted to the rear of the front panel adjacent to the PANEL
LIGHT. The high pressure switch activates above 1250 psi. If the HIGH PRESSURE SWITCH activates, the R.O. pump
will automatically shut down and the HIGH PRESSURE LAMP will come on. When the pressure drops, use the RESET
SWITCH to reset high pressure switch. Notify unit maintenance to troubleshoot the HIGH PRESSURE RELIEF VALVE.
c. Rupture Disc Assembly. The rupture disc assembly is located on the pipe between the R.O. PUMP and the pulse
dampener. The rupture disc is a thin sheet of metal that tears when the pressure goes above 1425 psi. Water is then
discharged through the six holes in the top of the assembly. Because the water is under such high pressure, it will make
a lot of noise, and water will be sprayed on the inside of the ROWPU. If the rupture disc assembly ever activates, press
the PUSH EMERGENCY STOP switch and open the REGULATE PRODUCT FLOW valve. When the pressure has
maintenance to troubleshoot the high pressure relief valve and the high pressure switch.
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