Precautions Against Frost; Guarantee Conditions; Operating Faults And Their Possible Causes - Pratissoli MF Serie Manual De Uso

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PRECAUTIONS AGAINST FROST

Follow the instructions in Chapter 12 in areas and
times of the year at risk of frost (see par. 12.1).
In the presence of ice, do not start the pump
for any reason until the circuit has been fully
defrosted, otherwise there can be serious
damage to the pump.
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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) insufficient 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.
- Outlet line is closed and thus prevents the
release of air trapped in the pump manifold.
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).
- Rpm lower than the nominal speed;
- Excessive leakage of the pressure control valve.
- Worn valves.
- Excessive internal leakage from 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:
- Service (nozzle) demand is or has become higher
than pump capacity.
- Insufficient pump speed.
- Excessive internal leakage from pressure seals.
- Imperfect functioning of the pressure control
valve.
- Worn valves.
The pump is overheated:
- The pump is working at excess pressure or pump
speed is higher than the rated speed.
- Oil in the pump casing is not at level or not the
recommended type as detailed in chapter 7
(see par. 7.6).
- 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.
- Valves malfunction.
- Irregular drive transmission.
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