Interpump Group Pratissoli WK Serie Manual De Uso Y Mantenimiento página 32

14 GUARANTEE CONDITIONS
The guarantee period and conditions are contained in the
purchase agreement.
The guarantee will in any case be invalidated if:
a) The pump is used for purposes other than for those agreed
upon.
b) The pump is fitted with an electric or combustion motor
with performance exceeding those indicated in the table.
c) Safety devices are decalibrated or disconnected.
d) The pump is used with accessories or parts not supplied
by Interpump Group.
e) Damage has been caused by:
1) improper use
2) failure to follow maintenance instructions
3) any use different from that described in the operating
instructions
4) lack of sufficient flow rate
5) defective installation
6) improper positioning or sizing of pipes
7) unauthorised design modifications
8) cavitation.
15 OPERATING FAULTS AND THEIR
POSSIBLE CAUSES
The pump does not produce any noise upon
start-up:
- The pump is not primed and is running dry.
- No suction water.
- Valves are blocked.
- The outlet line is closed and does not allow air
present in the pump head to come out.
The pump pulsates irregularly:
- Air suction.
- Insufficient supply.
- Bends, elbow bends, fittings along the suction
line are choking the passage of liquid.
- The suction filter is dirty or too small.
- The booster pump, where installed, is supplying
insufficient pressure or flow rate.
- The pump is not primed for insufficient head or
the outlet is closed during priming.
- The pump is not primed due to valve jamming.
- Worn valves.
- Worn pressure seals.
- Imperfect functioning of the pressure control
valve.
- Problems on the transmission.
The pump does not supply the nominal flow rate/
excessive noise:
- Insufficient supply (see various causes as above).
- The number of rpms is less than the nominal rate;
- Excessive leakage of the pressure control valve.
- Worn valves.
- Excessive leakage of the pressure seals.
- Cavitation due to:
1) Improper sizing of suction ducts/undersized
diameters.
2) Insufficient flow rate.
3) High water temperature.
The pressure supplied by the pump is insufficient:
- Use (nozzle) is or has become higher than the
capacity of the pump.
- The number of rpms is insufficient.
- Excessive leakage of the pressure seals.
- Imperfect functioning of the pressure control
valve.
- Worn valves.
The pump is overheated:
- The pump is working in pressure excess or the
number of rpms is higher than the nominal rate.
- Oil in the pump casing is not at level or not the
recommended type as detailed in chapter 7 (see
par. 7.6).
- Excess belt tension or joint or pulley alignment is
incorrect.
- Excessive pump tilt during operation.
Vibrations and shock to pipes:
- Air suction.
- Imperfect functioning of the pressure control
valve.
- Valve malfunction.
- Non-uniformity in the transmission motion.
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