Dover PSG Wilden Pro-Flo 230/SSPPP, Engineering, Operation & Maintenance

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WIL-11570-E-03 Wilden ®
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Suggested Installation, Operation, Maintenance and Troubleshooting
Troubleshooting
Pump will not run or runs slowly.
1. Remove plug from pilot spool exhaust.
2. Ensure that the air inlet pressure is at least 0.4 bar (5 psig)
above startup pressure and that the differential pressure
(the difference between air inlet and liquid discharge
pressures) is not less than 0.7 bar (10 psig).
3. Check air inlet filter for debris (see "Suggested
Installation, Operation, Maintenance and
Troubleshooting" on page 12).
4. Check for extreme air leakage (blow by) that would
indicate worn seals/bores in the air valve, pilot spool and
main shaft.
5. Disassemble the pump and check for obstructions in the air
passageways or objects that would obstruct the movement
of internal parts.
6. Check for sticking ball check valves.
a. If material being pumped is not compatible with pump
elastomers, swelling may occur. Replace ball check
valves and seals with proper elastomers.
b. Also, as the check valve balls wear out, they become
smaller and can become stuck in the seats. In this case,
replace balls and seats.
7. Check for any broken inner piston that would cause
the air valve spool to be unable to shift.
Pump runs, but little or no product flows.
1. Check for pump cavitation. Slow pump speed down to
allow thick material to flow into liquid chambers.
2. Verify that vacuum required to lift liquid is not greater than the
vapor pressure of the material being pumped (cavitation).
3. Check for sticking ball check valves.
a. If material being pumped is not compatible with pump
elastomers, swelling may occur. Replace ball check
valves and seals with proper elastomers.
b. Also, as the check valve balls wear out, they become
smaller and can become stuck in the seats. In this
case, replace balls and seats.
Pump air valve freezes.
1. Check for excessive moisture in the compressed air.
a. Either install a dryer or a hot air generator for
compressed air.
b. Alternatively, you may use coalescing filter to remove
the water from the compressed air in some applications.
Air bubbles in pump discharge.
1. Check for a ruptured diaphragm.
2. Check tightness of outer pistons (see
Disassembly/Reassembly on page 15).
3. Check tightness of fasteners and integrity of O-rings
and seals, especially at intake manifold.
4. Ensure pipe connections are airtight.
Product comes out air exhaust.
1. Check for a diaphragm rupture.
2. Check the tightness of the outer pistons to the shaft.