Pratissoli VFH Serie Manuel D'utilisation Et D'entretien page 32

• Insert the free ends of the suction pipes and the high
pressure exhaust pipe inside the container.
• Switch on the diaphragm pump.
• Pump the emulsion until it exits from the high pressure
exhaust pipe.
• Continue pumping for at least another minute.
• Stop the pump and remove the previously connected
pipes.
• Clean, grease and plug the connections on the pump
head.
The characteristics of the emulsion can be strengthened if
necessary by adding, for example, Shell Donax.
13 PRECAUTIONS AGAINST FROST
Follow the instructions in Chapter 12 in areas and
times of the year at risk of frost (see par. 12.2).
In the presence of ice, do not run the pump
for any reason until the circuit has been fully
defrosted, in order to avoid serious damage to
the pump.
14 WARRANTY 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 the agreed
purposes.
b) The pump is driven by an electric motor or internal
combustion engine having performance values exceeding
those shown in the table.
c) The safety devices have been tampered with or they have
been disconnected.
d) The pump has been used with accessories or spare 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 jammed.
- The outlet line is closed and does not allow the
release of air present in the pump manifold.
Pump pulsates irregularly:
- Air suction.
- Insufficient supply.
- Bends, elbows, fittings on the suction line are
choking the passage of liquid.
- Suction filter is dirty or too small.
- The booster pump, where installed, is supplying
insufficient pressure or flow rate.
- The pump is not primed due to 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).
- Pump speed is below the rated speed;
- Excessive internal leakage of pressure control
valve.
- Worn valves.
- Excessive leakage from 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:
- The user flow (nozzle) is or has become greater
than the pump capacity.
- Insufficient revolutions per minute.
- Excessive leakage from the pressure seals.
- Imperfect functioning of the pressure control
valve.
- Worn valves.
Pump overheats:
- The pump is working in overpressure conditions
or pump rpm is higher than the nominal value.
- 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 or hammering on pipes:
- Air suction.
- Faulty operation of pressure control valve.
- Valves malfunction.
- Non-uniformity of transmission motion.
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