15
T
T
T
R
R
R
O
O
O
U
U
U
B
B
B
L
L
L
E
E
E
S
S
S
H
H
H
O
O
O
O
O
O
T
T
T
I
I
I
N
N
N
G
G
G
PROBLEM
PROBABLE CAUSE
REMEDY SUGGESTED
Motor runs, but pump fails
to suck liquid
1. After starting, pump is
not fully filled with water
2. During suction the filled
water reduces due to
opening of the water
discharge port at the
pressure side
3. Insufficient tight of suc-
tion pipe
1.Fully filling water in pump
2.Filling water into pump.
When restarting pump,
raising the pressure side
pipe to 1m vertically from
the pump and keeping
the distance till the pump
starts to make suction
3.Checking pump fittings,
such as suction pipe con-
nector, high-pressure
pipe connector, clamping
ring, suction pipeline, in-
cluding seals made of
PTFE or hemp fiber. Only
under vacuum may the
pump make suction.
4.Cleaning the filter screen
and bottom valve at the
suction port.
5.During pump suction,
opening the water dis-
charge port (tap or noz-
zle)
6.Fully filling water into the
entire suction pipeline or
making recheck after at
least 7 minutes from start
of pump.
7.Reducing suction height
(max. 7 m)
8.Check water level of well
or pond, or extending the
suction pipeline, if possi-
ble.
4. Blocking of filter screen
of bottom valve at suc-
tion port
5. Failure to remove air
from pressure pipe due
to closing of the water
discharge port
6. Failure to delivery in the
waiting time
7. Excessively suction
height
8. Bottom valve’s failure to
make suction
