La San Marco NEW 105 TOUCH Emploi Et Entretien page 84

PRoBlEM
9. • Overfill alarm
10. • The machine is switched
on (the main switch is in
position 1 or 2 and the
signal light is lit) but the
electronic control is out
of order.
11. • The machine feeds water
from one serving unit
although the serving has
not been selected.
12. • The steamer discharges
only small quantities of
steam or water droplets.
13. • Small drops flow out of
the water tap.
14. • The unit emits a whistle
after serving the coffee.
15. • The filter cup comes off
the serving unit.
16. • When coffee is being
served, some of it drips
out of the edge of the
filter cup.
17. • Water leaking from the
drain of the serving unit
solenoid.
18. • Light cream (the coffee
flows out of the spout
rapidly).
CaUSE
• Malfunction in automatic level
circuit.
• Leak in button for manual
water filling.
• Leak in heat exchangers.
• The electric wiring of the
electronic control unit is
defective.
• The electronic control unit is
defective.
• Solenoid and/or pump fed
continuously.
• Tap needs adjustment.
• Worn gasket on tap.
• Leak in solenoid valve
• Faulty operation of expansion
valve.
• high pump pressure.
• Gasket under holder is worn.
• Gasket under holder is worn.
• Malfunctioning unit solenoid.
• Water leaking from unit cooling
system.
• Coarse grinding.
• Low pressing pressure.
• Small quantity of ground
coffee.
• Water temperature below 90°C
• Pump pressure above 9 bar.
• Sprinkler filter on unit clogged.
• Filter holes widened (filter cup).
SolUtion
• Check the hydraulic circuit of the
autolevel.
• Check the electrical wiring, the
electronic control unit and its
components.
• Replace the electronic control unit.
• Control unit relay powered
continuously.
• Replace the electronic control unit.
• Tap needs adjustment.
• Replace the gasket.
• Check the solenoid valves (hot
and cold water) and replace as
necessary.
• Check the expansion valve and if
necessary replace it. Calibrate the
valve at 12 bar.
• Check the pump operating pressure.
Calibrate the pump at 9 bar.
• Replace the gasket.
• Clean the serving unit and the filter
cup.
• Replace the gasket.
• Clean the serving unit and the filter
cup.
• Check the unit solenoid valve. Check
the plunger on the solenoid valve
and clean it.
• Replace the automatic level solenoid
valve.
• Check the small cooling tube and the
related seals of the dispensing unit
(NeW 105 TOUCh DTC).
• Finer grinding.
• Increase the pressure.
• Increase the quantity of ground
coffee.
• Adjust valve (flow variator) of the
group to a higher number or increase
boiler pressure.
• Decrease the pump pressure.
• Check and clean with blind filter or
replace.
• Check and replace filter.
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