Main Defects Caused By The Incorrect Use Of The Equipment - La San Marco 95 SERIES Use And Maintenance Manual

MAIN DEFECTS CAUSED BY THE INCORRECT USE
PROBLEM
1 The boiler fills with water,
with venting from the
safety valve
2 Operation of the safety
valve with venting of steam
3 The machine does not heat
4 Water is not coming out of
one unit
5 The settings for the amount
of coffee dispensed do not
remain as set on one or all
the units
6 The machine will not accept
programming for unit 1
and therefore copying to
the other units
7 Alarm signalled by flashing
of the single strong coffee
LED for the unit used
8 Alarm signalled by flashing
of the double strong coffee
LED of all the units and the
tea unit
9 Dispensing of one or more
measures to a coffee unit or
the tea unit starts up at
random and on its own
10 The machine is switched on
and is heating normally;
the mains power light is on
but none of the electronics
are working
11 In the case of an electronic
machine, unit 1 or unit 2 are
operating continuously even
though dispensing for these
units has not been selected
12 In the case of a semi-auto-
matic machine, one unit is
operating continuously
13 Small amounts of steam or
drops of water coming from
the steam tap
54
F O R T H E U S E R
OF THE EQUIPMENT
CAUSE
• Leak in one of the boiler filler
pipes or in one of the unit circuits
• Increase in boiler pressure to 2-
2.5 bar due to incorrect operation
of the heating system because the
element is constantly energised
• The element is not being supplied
with power, or has burnt out or
there is no mains power
• Water circuit blocked
• Failed solenoid valve
• Coffee ground too fine and
maybe amount dispensed too
large for the type of filter used
• Malfunction of the dispenser
metering circuit on one or all
units
• Leak at unit solenoid valve
• Malfunction of the meter for unit
1 or of the electronic control unit
• The metering signals for the unit
meter have not reached the elec-
tronic control unit
• The water level in the boiler has
not been topped up within the set
time
• Loss of normal free travel of one
or more of the pushbuttons due to
a build-up of material on the out-
side or infiltration of water or
steam inside the card
• The electronic control unit is not
being energised or has burnt out
• The solenoid valve and pump (or
only the solenoid valve) are being
permanently energised
• Circuit permanently energised
• Adjusting screw not adjusted
• Tap washer worn
SOLUTION
• Check the automatic level circuit
• Check the manual fill button
• Check for leaks from the heat exchanger
• Check the pressure switch in the electrical contacts in the
mechanical part and in the tube which links it to the steam
pressure in the boiler
• For machines with electronic temperature control, check all
the system components, such as sensor, triac, control unit,
connecting wires and reset the trimmer if necessary
• Check that the mains power is on
• Check that the main switch is not damaged
• Check that the safety thermostat on the heater element has
not tripped
• Check the pressure switch for correct electromechanical
operation
• For machines with electronic temperature control, reset the
trimmer, check the sensor, the triac, the control unit and
the sensor-triac-control unit connecting wires
• Check that the injector, the top circulation tube, the jet and
the solenoid valve are not blocked; for machines with
electronically controlled dispensing, also check the volume
meter and that its cut-off tap is open
• Check the electromechanical components of the solenoid
valve, the control unit to coil connecting wires and the
control unit fuse
• Check the dispensing and grinding settings
• Programme different settings for each unit
• If the problem persists, replace the meter for the unit
involved
• Replace the solenoid valve
• Check the connection between the meter for unit 1 and the
control unit
• If the connection is satisfactory replace the meter for unit 1
or replace the control unit
• Meter or corresponding electrical circuit damaged
• Check the electromechanical components of the solenoid
valve, the control unit to coil connecting wires, the
corresponding fuse and the control unit itself
• Automatic level circuit blocked or no water supply
upstream
• Automatic level solenoid valve and corresponding electrical
circuit damaged
• Clean all the push buttons
• Dry the printed circuit
• Check that the switch located above the main switch on
the machine for supply to the electronic control unit is not
tripped (if it is, the green light will be on)
• Check the control unit triac protection fuses
• Emergency switch tripped
• Relay short-circuited and welded
• In the case of model 95-26, button E plus button 1 or 2 are
depressed
• Contact in the ON switch welded or wires incorrectly
connected
• If the machine has only recently been installed or if the
washer has recently been replaced, unscrew the adjusting
screw
• If the machine is not new, replace the washer