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1. Troubleshooting
Troubles
Liquid can not
be sucked
•
Lack of priming
liquid
•
Dry running
•
Foot valve is cl-
ogged by foreign
matters.
•
Stop pump and reple-
nish pump with liquid to
re-start.
Primed liquid drops
quickly
•
Clean foot valve
•
Check if foreign matters
are not adhered to valve
seat.
When disch. valve
closed
After starting, pres-
sure drops as soon as
discharge valve is
opened.
•
Air is sucked from
suction pipe or gas-
ket.
•
Check if connected
flanges are completely
sealed.
•
Check if liquid level of
tank is not excessively
lowered.
•
Disconnected ma-
gnet coupling
•
Check amperage to see
if motor is not over-
loaded.
•
Check if foreign matters
do not lock imp-eller or
magnet capsule
•
Check if voltage is nor-
mal.
Press. gauge shows
low pressure
•
Low pump speed
•
Reverse rotation
•
Check wiring or motor.
•
Interchange wiring con-
nection.
D i s c h a r g e
capacity is
small.
Pressure gauge &
vacuum gauge indi-
cates normal figure.
•
Strainer is clog-ged
by foreign matters.
•
Remove foreign matters.
•
Air pocket in suc-
tion piping
•
Check and remedy suc-
tion piping.
•
Foreign matters are
clogged at impeller
inlet.
•
Remove foreign matters.
•
Air is sucked in
from suction pipe or
gasket.
•
Check connection part
of pipes and retighten it.
•
Foreign matters
clog at discharge
side.
•
Remove foreign matters.
•
Remove foreign matters
or scales in piping.
Symptom on pump
Cause
Countermeasures
When disch. valve
opened
Press. gauge & vacu-
um gauge indicate
zero.
Pressure gauge vi-
brates and drops to
zero.
Vacuum gauge indi-
cates high figure.
Vacuum gauge indi-
cates very high figure.
Pressure gauge &
vacuum gauge vi-
brate.
Vacuum gauge indi-
cates hign but pres-
sure gauge indicates
normal.
•
There are resis-
tance such as air
pocket etc. in suc-
tion piping.
•
Check if there is not pro-
truded section in suction
piping.
