Pump Does Not Perform Any Suction Despite Full Stroke Movement And Venting; Metering Stroke Is Not Completed Although An Air Pressure Of 6 Bar Is Present; Liquid Leaks At The End Disc - ProMinent Pneumados PNDb Series Operating Instructions Manual

Possible cause
Abhilfe
Possible cause
Remedy
Possible cause
Remedy
ProMinent ®
12.2 Pump does not perform any suction despite full stroke movement and
venting
Crystalline depositions because of drying up of the valves
Remove the suction hose from the store tank and thoroughly rinse the liquid end
If required, reduce the suction height or support first suction action with filled suction hose in
feed operation
The metering solution can also be taken in using a disposable syringe connected at the
pressure valve
If the fault is not remedied, the valves are to be removed and cleaned
The valve seat in the suction and pressure valve can be pushed out with a mandrel ø 3mm.
12.3 Metering stroke is not completed although an air pressure of 6 bar is
present
Oil has collected in the pressure chamber of the housing
Empty pressure chamber
For this purpose, turn the pump by 180° until the compressed-air connection points to the
bottom (if required, disconnect the suction and metering line at the pump head first)
Operate compressed air continuously for approx. 3 seconds for liquid (oil) to be able to collect
at the bottom of the pressure chamber at the connection
Then depressurise and discharge the liquid (oil) through the relief connection "R" at the control
valve (see Chapter 2.4.1)
Repeat this step several time until no liquid discharges any longer.
12.4

Liquid leaks at the end disc

The delivery unit leaks at the metering diaphragm
Re-tighten the screws at the liquid end crosswise
IMPORTANT
Observe the tightening torques for the screws!
All pump types: 4.5 to 5 Nm!
If liquid is still leaking, the diaphragm has ruptures and must be replaced.
(see Chapter 12.5)
Troubleshooting / Remedy
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