18. Defects - Malfunctions
Interventions by a specializes technician
PROBLEM
Dispensing slow.
Coffee burnt and cold.
Cream very dark, with tendency of
formation of an "eye".
Dispensing slow, coffee burnt.
Pressure gauge pump lower than 9 bar.
Drainage tube leaks when group is at rest
(defect only on one group).
Coffee dispensed normally.
Group at rest
Dispensing valve gasket fails rapidly.
Water leak from the drainage tube.
Coffee dispensed normally.
Defect on all groups.
Group at rest.
Continuous loss of cold water in the
drainage tray. Groups do not dispense
any more coffee and the pressure gauge
pump shows low values.
Group in operation.
Drainage tube leaks.
No coffee.
Group in operation.
Loss of cold water in drainage tray.
Coffee bland.
Dispensing slow.
Machine does not go into pressure or
reaches pressure level slowly.
Groups function normally.
Pressure gauge pump does not give
correct pressure reading (8 ÷ 9 bar).
Pump does not reach pressure level.
No dispensing.
Pump noisy.
CAUSE
Coffee grounds too fine.
Low pressure in pump.
Mesh filter above spout dirty.
Spout partially blocked.
Pump out of calibration.
Pump with reduced capacity.
Dispensing valve does not hold.
Expansion valve with calibration too high
(above 12 bar).
Expansion valve remained open.
Drainage valve does not hold.
Expansion valve out of calibration (opens
at less than 9 bar).
No electricity.
Automatic switch gone off.
Resistances burned.
Electric circuit to resistance interrupted.
No water in boiler.
Pressure gauge defective.
Motor does not work:
- No electricity.
- Capacitor burnt.
- Microswitch burnt.
- Motor burnt.
Check valve pump open.
By pass valve completely opened.
Pump defective.
No water in system.
34
SOLUTION
If this defect is not corrected immediately, the
water softener runs out long before the expiry
time, with consequent scale deposit.
If this defect is not corrected immediately,
the water softener runs out long before
the expiry time, with consequent scale
deposit.
If this defect is not corrected immediately,
the water softener runs out long before
the expiry time, with consequent scale
deposit.