Problem Solving - La San Marco Duale Class Bedienungs- Und Wartungsanleitung

13. Problem solving

PROBlEM
1. The boiler is full of water
and the water flows out of
the safety valve. The water
level in the optical level is
higher than the MAx.
2. Intervenes the safety valve
by venting the steam.
The gauge indicates the
pressure of the boiler
exceeding 1.8 bar.
3. The machine was started
properly but the water in the
boiler does not warm up.
4. No dispensing water from
a dispensing unit by lever
group.
5. No dispensing water
from one of the electronic
dispensing unit.
CAUsE
• The solenoid valve of the
automatic filling always
remains open.
• There is a fault in the manually
valve for filling.
• Failure to the control system of
resistance (electrical resistance
is always powered).
• Failure of the safety
thermostat.
• Increased pressure in the
boiler (intervention of the
safety valve 1.8bar)
• The electric heating element is
defective or is not connected.
• Main switch turned to position 1.
• Coffee ground too fine or
excessive quantity for type of
filter used.
• The valve of the lever
dispensing unit does not open
because it is not properly
adjusted.
• The water level is less than the
MIN.
• Clogged water circuit.
• Coffee ground too fine or
excessive quantity for type of
filter used.
• The solenoid valve of a
dispensing unit does not open
because is broken.
• Clogged water circuit.
sOlUTiOn
• Close the main water valve and
contact a qualified service technician
authorized.
• The authorized qualified technician
must check the correct operation
of the filling solenoid valve, the
electronics that control the automatic
level and the eventual failure of the
manually valve for filling.
• Switch off the machine by putting the
power switch to the 0 position and
contact a qualified service technician
authorized.
• The authorized qualified technician
must check the electrical wiring that
feeds the resistance, the temperature
control system switch and safety
thermostat.
• The main switch must be turned to
position 2.
• The authorized qualified technician
must check the electrical wiring that
supplies the resistance. It also needs
to check if the thermostat is tripped
safety of the resistance and check
for proper operation.
• Adjust the grinding coarseness and/
or the quantity of ground coffee.
• The authorized qualified technician
must check and verify that the valve
of the unit is properly adjusted.
• Check that the water level is higher
than the MAx.
• The authorized qualified technician
must check and verify that the
hydraulic circuit is not obstructed or
there may be a pump failure.
• Adjust the grinding coarseness and/
or the quantity of ground coffee.
• Check that the valves of volumetric
meters are in "open" position.
• The authorized qualified technician
must check and verify the volumetric
meters and them valves.
• The authorized qualified technician
must check the solenoid valve of the
dispensing unit, its wiring and the
fuse in the electronic control unit.
• The authorized qualified technician
must check and verify that the
hydraulic circuit is not obstructed or
there may be a pump failure.
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