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 goes up.
Causes
a
Not enough priming water
a
Dry operation.
a
Foreign matter is clogging
foot valve.
a
Air enters through suction
pipe or gasket section.
a
Magnet coupling has
disconnected.
a
Speed of pump is too low.
a
Pump rotates in reverse
direction.
a
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 connecting
flange in suction piping is sealed
airtight.
K
Check whether suction liquid
level is abnormally lowered.
K
Stop pump and use screwdriver
to check for easy and smooth
rotation of motor fan.
K
Measure current level to check
for overload condition.
K
Check whether the voltage level
is normal.
K
Check for foreign matter
between impeller and magnet
capsule.
K
Check wiring and motor and
make necessary repairs.
K
Exchange wires.
K
Eliminate the foreign matter in
strainer.
Symptom on pump
1. Causes of Trouble and Troubleshooting
- 30 -
Refer to "1 causes of Trouble and Troubleshooting" Consult supplier for more information. If you find any troubles,
turn off the power supply immediately.
