14
Troubleshooting
1. Insufficient pumping and discharge amount
2. Overheating Motor
3. Pump vibration
Insufficient pumping and discharge amount
Insufficient discharge amount
No pumping when discharge valve
is open
No pumping when priming water is
fed into the pump
Pump
rotates in
reverse
Air trapped
in suction
pipe
Resistance
in discharge
pipe
Air entering
from suction
pipe or
connection
area
Step-out of
magnet
coupling
Insufficient
amount of
priming
water
Foreign
object in
suction pipe
Switch
motor wiring
Inspect
suction pipe
Remove
foreign
object from
discharge
pipe and
check for
pipe damage
Inspect
connection
area of
suction pipe.
Check liquid
level of pit
tank
Check
inside the
pump for
foreign
objects.
Check that it
is not in an
overloaded
state.
Supply
priming
water.
Discharge
all air in the
pump.
Clean
suction pipe
Overheating motor
Excessive output
Check if specific gravity and
viscosity of liquid used match the
specifications
Check if motor voltage and
frequency match the specifications
Operating temperature is high
Lower the operating temperature
Pump vibration
Unstable
installation
location
Loose bolts
on the pump
Foreign
object in
suction pipe
Worn pump
bearing
Damaged
pump shaft
Pump impeller
in contact with
stationary part
Worn motor
bearing
Re-install it
Tighten bolts
Remove
foreign
objects and
clean
Replace
pump
bearing
Replace
pump shaft
Replace
impeller
Replace
bearing or
motor
Min. liquid level is low
Increase to min. liquid level
