General Pump VH - Manual (Page 17)

GENERAL PUMP
A member of the Interpump Group
VH SERIES
Page 17
17. TROUBLE SHOOTING
THE PUMP DOES NOT PRODUCE ANY
NOISE: the pump is not primed
and is running dry!
- No water in the inlet line
- The valves are blocked
- The pressure line is closed and does
not allow the air to get out the fluid
end.
THE PUMP KNOCKS:
- Air suction.
- Insufficient feeding:
- bends, elbows and fittings along the
suction line throttle the amount of
water which passed through.
- too small inlet filter.
- dirty inlet filter.
- the feeding pump, where provided is
not of the suitable type or provides
insufficient pressure or volume.
- The pump is not primed due to
insufficient feeding or the delivery line
is closed during start up.
- The pump is not primed because some
valves are stuck (i.e pump inactivity
for long time).
- Jammed or worn out valves.
- Worn out pressure packings.
- The pressure regulating valve does not
work properly.
- Clearance in the drive system.
- RPM are higher than rated.
THE PUMP DOES NOT DELIVER THE
RATED VOLUME:
- Insufficient feeding (due to the cause
listed above).
- RPM are less than rated.
- Excessive amount of water by-passed
by the pressure regulating valve.
- Worn out valves
- Excessive leakage from pressure
packings
INSUFFICIENT PUMP PRESSURE:
- The nozzle is (or has become) too large.
- RPM are less than rated
- Excessive leakage from pressure
packings
- Excessive amount of water by-passed
by the pressure regulating valve or
faulty valve operation.
- Worn out valves.
EXCESSIVE WATER LEAKAGE FROM
THE PUMP:
- Pressure packing are excessively worn
out (due to normal wear or excessive
cavitation).
- Worn out plungers
OVERHEATED PUMP:
- The direction of rotation is not correct.
- Pump is overloaded (pressure or RPM
over the rated values).
- The oil level is too low or the oil is not of
a suitable type or fully used
- Water in the oil
- Excessive belt tension or incorrect
alignment of the joint (where provided).
- Excessive inclination of the pump
during operation.
PIPE VIBRATIONS OR KNOCKING:
- Air suction.
- The pressure regulating valve does not
work properly.
- The by-pass line is undersized.
- Jammed up valves.
- Drive transmission motion is irregular.