Troubleshooting
User Manual Chemical centrifugal pumps with mechanical seal V080716
33
No or too low flow
rate
Discharge and/or suction
line not (entirely) filled with
liquid
Fill the discharge and/or
suction line.
The NPSH
available
is too low •
Raise the suction head.
•
Lower the product.
•
Make the suction line
shorter or more straight.
The suction line is not
correct
Improve the suction line.
Air pockets in the discharge
line
Check the connections on
leaks.
The valves are not
completely open
Open the valves.
Strainer or suction and
discharge line are clogged
Clean the strainer. Clean the
suction and discharge line.
Direction of rotation is not
correct
Check the direction of rotation.
See §
.
Shaft seal leaks
The system pressure is too
high
Adjust the system pressure.
The diaphragm or O-ring is
damaged or not sealing
properly
Replace the diaphragm or O-
ring.
There is some impurity
between the seal rings
Clean the seal rings.
The seal rings are worn
Replace the seal rings.
Problem
Possible cause
Solution