6-2
Problem
Cause (Reference page)
Action (Reference page)
Done by *
The pump starts,
but cannot
achieve the
specified
discharge rate
and the specified
head.
The rotation speed is low.
Check with the tachometer.
User
The sluice valve is closed.
Open the sluice valve.
User
The strainer on the suction port is clogged. Check and clean the strainer.
User
The suction port is exposed above the
liquid level. (3-2)
Adjust the liquid level, for example, by
refilling the tank with the liquid or by
lowering the installation position of the
pump.
User
There is a leak in the discharge pipe.
Check and repair the pipe.
Vendor
Overheat of
bearing
The bearing is worn or damaged. (5-1)
Replace the bearing. (5-1)
Contact the vendor because disassembly
and inspection are required.
Vendor
The grease is deteriorated. (5-1)
Incorrect installation of the pump and the
piping (3-2)
Check and correctly install them.
User
Unusual noise
and unusual
vibration of the
pump
The bearing is worn or damaged. (5-1)
Replace the bearing. (5-1)
Contact the vendor because disassembly
and inspection are required.
Vendor
The motor is running in open-phase
condition.
Check the wiring.
User
The impeller is clogged with foreign matter,
thus leading to imbalanced load.
Disassemble and check.
Contact the vendor because disassembly
and inspection are required.
Vendor
Cavitation has occurred.
Contact the manufacturer and vendor.
User
Incorrect installation of the pump and the
piping (3-2)
Check and correctly install them.
User
Water hammer
occurs.
Hammering has occurred when the valve is
rapidly opened and closed.
Provide a pressure damper (e.g.
accumulator).
User
* The persons who take the Action are specified here (Done by) only as a guide because the extent of
actions that can be taken is different depending on the user.
If you have anything unclear—even about the problems whose actions are to be done by User, ask the
vendor or contact TERAL.
