General Pump VF Owner Manual - Manual (Page 14)

GENERAL PUMP
A member of the Interpump Group
VF SERIES
Page 14
13. PRECAUTIONS AGAINST FREEZING
In areas and periods of the year where there is
risk of freezing, follow the instructions indicated
in Chapter 12 (see paragraph 12.2).
In the presence of ice, in no case must the
pump be started until the entire circuit has
been completely thawed out; not complying
with this indication may cause serious
damage to the pump.
14. WARRANTY TERMS
The duration and the terms of the warranty are contained
in the purchase contract. The warranty is void if:
a) The pump has been used for purposes that differ
from that agreed.
b) The pump has been fit with an electric or diesel
engine with performance greater than that indicated
in the table.
c) The required safety devices were maladjusted or
disconnected.
d) The pump was used with accessories or spare parts
not supplied by General Pump.
e) Damage was caused by:
1) improper use
2) the non-observance of maintenance instructions
3) use not compliant with operating instructions
4) insufficient flow rate
5) faulty installation
6) incorrect positioning or sizing of the hoses
7) non-authorized design changes
8) cavitation
15. TROUBLESHOOTING
The pump does not produce any noise at
start-up:
• The pump is not primed and is running dry
• There is no water in the inlet line
• The valves are blocked
• The delivery line is closed and does not allow
the air in the pump to be discharged
The pump pulses irregularly (knocking):
• Air suction
• Insufficient feeding
• Bends, elbows, fittings along the suction line
obstruct the fluid’s passage
• The inlet filter is dirty or too small
• The booster pump, where provided, supplies
insufficient pressure or flow rate
• The pump is not primed due to insufficient
head or the delivery line is closed during
priming
The pump pulses irregularly (knocking):(cont)
• The pump is not primed due to valve seizing
• Worn valves
• Worn pressure packings
• Incorrect operation of the pressure adjust
ment valve
• Transmission problems
The pump does not deliver the rated flow / is
noisy:
• Insufficient feeding (see the causes listed
above)
• RPM are less than the rated flow
• Excessive amount of water by-passed by the
pressure adjustment valve
• Worn valves
• Leakage from the pressure packings
• Cavitation due to:
1) Wrong sizing of the suction hose/
undersized diameters
2) Insufficient flow rate
3) High water temperature
Insufficient pump pressure:
• The nozzle (or has become)too large
• Insufficient RPM
• Leakage from the pressure packings
• Incorrect operation of the pressure
adjustment valve
• Worn valves
Overheated pump:
• The pump is overloaded (pressure or RPM
exceed the rated values)
• Oil level is too low, or the oil is not of a suit
able type, indicated in Chapter 7 (see para-
graph 7.4)
• Excessive belt tension or incorrect alignment
of the joint or the pulleys
• Excessive inclination of the pump during
operation
Hose vibrations or knocking:
• Air suction
• Incorrect operation of the pressure
adjustment valve
• Valve malfunction
• Irregular drive transmission motion
Ref 300662 Rev.C
06-12