1. Causes of Trouble and Troubleshooting
- 32 -
Problem
Liquid is not
lifted.
Discharge
volume is
small.
When Discharge
Valve is Opened
Pressure gauge
and vacuum
gauge indicate
‘zero’.
Points of
pressure gauge
and vacuum
gauge swing
but return to
zero at once.
Pointer of
vacuum gauge
indicates a high
value.
When Discharge
Valve is Closed
Water goes
down at once
when priming
is carried out.
Pressure is
reduced if
discharge valve
is opened after
start-up step.
Pointer of
pressure gauge
never rises.
Cause
K
Not enough priming wa-
ter
K
Dry operation.
K
Foreign matter is clog-
ging foot valve.
K
Air enters through suction
pipe or gasket section.
K
Magnet coupling has dis-
connected.
K
Speed of pump is too low.
K
Pump rotates in reverse
direction.
K
Strainer is clogged with
foreign matter and liquid
passage is blocked.
Inspection and Measures
K
Stop pump, feed sufficient
priming water, and restart
pump.
K
Clean foot valve.
K
Check whether seat is clogged
with foreign matter.
K
Check again whether conn-
ecting flange in suction piping
is sealed airtight.
K
Check whether suction liquid
level is abnormally lowered.
K
Measure electric current level
to check for overload condition.
K
Check whether the voltage
level is normal.
K
Check for foreign matter
between impeller and casing.
K
Check wiring and motor and
make necessary repairs.
K
Exchange wires.
K
Eliminate the foreign matter in
strainer.
Symptom on pump
Refer to "1. Causes of Trouble and Troubleshooting". Consult supplier for more information.
If you find any troubles, turn off the power supply immediately.
