Problem Solving - La San Marco TOP 85 Serie Manual De Uso Y Mantenimiento

18. Problem solving

PROBlEM
1.
• The boiler is full of water
and the water flows out
of the safety valve.
2.
• The safety valve trips in
and vents the steam.
3.
• The machine was
started properly but the
water in the boiler does
not warm up.
4.
• There is no water
flowing from a serving
unit.
5.
• The programmed
servings of espresso
coffee are not constant
or vary on the different
units.
6.
• It is not possible to
program the serving
quantities on unit 1 and
to copy them on the
other units.
7.
• Displacement meters
alarm.
8.
• Autolevel alarm.
CAUSE
• One of the outflow lines from
the boiler or from a circuit of
the unit has a leak.
• Malfunction of electrical
system (the electrical heating
element is always connected).
• Pressure increase in the boiler
(the safety valve trips in at
2-2.5 bar).
• 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.
• Clogged water circuit.
• Defective solenoid.
• Abnormal operation of the
electronic control unit or of the
displacement counters.
• Leak from serving unit
solenoid valve.
• Water dispensers clogged.
• Abnormal operation or
defective displacement meter
of unit 1.
• Displacement meters jammed
or defective.
• Defective wiring.
• Water circuit of automatic
level without water.
• Main water supply valve
closed.
• Faulty autolevel solenoid.
SOlUTION
• Check the autolevel circuit, the
manual charging button, and the
boiler heat exchangers.
• Replace worn or damaged parts to
eliminate the leak.
• Check the wiring that feeds the
heating element and the pressure
switch.
• Check if the heating element is
connected to the power supply.
• Check if the heating element safety
thermostat has tripped in and check
its proper operation.
• The main switch must be turned to
position 2
• Adjust the grinding coarseness and/
or the quantity of ground coffee.
• Check that the injector, the upper
circulation pipe, the valve (flow
variator) of the group, the water
dispenser and the solenoid valve of
the group are not clogged.
• In the machines with electronic
metering, check the displacement
meter and its valves.
• Check the solenoid of the unit, its
wiring and the fuse in the electronic
control unit.
• Program the serving quantities
separately on each serving unit. If
the problem persists, replace the
displacement meter of the serving
unit affected.
• Replace the solenoid valve of the
serving group.
• Check the water dispenser.
• Check the control unit-displacement
meters electrical wiring.
• Replace the displacement meter.
• Replace the volumetric counter.
• Check the wiring and its
connections, the control unit and the
fuses.
• Check the hydraulic circuit of the
autolevel.
• Check if the on-off valve on the
water supply is open.
• Replace the autolevel solenoid.
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