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Pressure
Symptom
Solution
System pressure
too low
Check the following:
Pressure gauge calibration.
Ensure tank outlet valve is open.
Ensure pump inlet and outlet tubing are
connected correctly. Ensure Sta-Pure
(white) tubing is connected from pump
outlet to feed in port (FEED IN).
If the fluid moves back and forth in the
pump inlet or pump outlet tubing, par-
ticulates may be impairing the pump check
valves from closing. Ensure pump check
valves are clean. See check valve flushing
procedure in maintenance section “Pump
check Valve Flushing” of this manual
If flushing the check valves does not
eliminate the problem, replace pump check
valves. See check valve replacement proce-
dure in maintenance section “Diaphragm
Pump Maintenance” of this manual
System Pressure
too high
Check the following:
Pressure gauge calibration
The retentate back-pressure valve is closed
