No pumping can be done, insufficient water volume, insufficient pressure.
Check the direction of rotation and motor r.p.m.
3
Forward rotation.
Reverse rotation.
Normal motor r.p.m.
Insufficient pressure.
Rewire two phases of
the three phase.
Abnormally slow motor
r.p.m.
Go to
Insufficient water volume.
Insufficient closed valve
pressure.
Can prime.
Cannot prime.
Insufficient air bleeding.
Lowered pump capacity
due to worn air suction
pump impeller or casing.
Normal closed valve pressure.
Low suction pressure.
Suction pressure is not low.
Air suction.
Excessive suction Pressure.
Suction pipe is clogged with
foreign particles.
Air remains in the suction
pipe.
1 Liquid is easily to foam.
2 Liquid temperature and
its specific gravity are
over its maximum
permissible limit.
3 Strainer, foot valve and
impeller are clogged with
foreign particles.
4 Worn impeller.
5 Suction pipe is too long
or narrow.
6 Liquid surface level is
deeper than priming limit.
1 Defective foot
valve/suction pipe.
2 Air from priming plug,
drain plug, flange part
and pipe.
3 Excess of self-priming
limit, or excessive
specific gravity.
4 Worn back/front
impeller.
5 Suction part is
clogged with foreign
particles.
6 Insufficient priming
water due to foreign
particles in a siphon
break hole.
7 Liquid that foams
easily, and liquid that
gives off gases easily.
8 Insufficient priming
water.
9 Air lock due to
improper air exhaust.
10 Strainer and foot
valve are clogged
foreign particles.
Unable to start.
1
19
