MNL- 0345
Page 90
Section 6
Base Edition
SECTION 6: MISCELLANEOUS
6.1 Pneumatic Valves and Controls
6.1.1
Nonadjustable Valves
The condensate drain valve, bleed valve and check valves are not adjustable. The condensate drain valve
and bleed valve have seats and seals which should be replaced if the valve leaks. Check valves are not
adjustable or repairable and must be replaced if they malfunction.
6.1.2
Pressure Maintaining Valve
The pressure maintaining valve is adjusted at the factory to the required pressure and does not normally
require maintenance or readjustment. The factory settings are:
Final Pressure Setting
Minimum PMV Setting
2,000-5,000 psi (138-350 bar)
2,175 psi (150 bar)
6,000 psi (414 bar)
3,000 psi (207 bar)
If readjustment does become necessary proceed as follows.
1. Loosen the locking nut (1).
2. Set the adjusting screw (2) to the required pressure using an appropriate hex type wrench.
3. Turn clockwise to increase pressure, counterclockwise to decrease pressure.
4. Determine if the PMV is properly adjusted:
a. Depressurize the final separator and purifier chamber by slowly opening the bleed valve.
b. Close the bleed valve and start the compressor.
c. Observe the final pressure gauge and note the pressure at which the valve opens (delivers).
d. If the pressure is not at the specified pressure ± 200 psi, readjust the PMV.
Figure 6.1-1
Pressure Maintaining Valve