Fault Diagnostics; Malfunctions - Bosch TCA640 Series Repair Instruction

7

FAULT DIAGNOSTICS

7.1

Malfunctions

7.1.1 Drawing coffee
Complaint
Coffee temperature too low
(Measure coffee temperature
5–10 mm under coffee outlet!)
Coffee temperature too high
Coffee has too little aroma
58300000120060_ARA_en_c.doc – 18.09.09
Cause?
►
Cold cup or cold milk in the cup
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Brewing system not prewarmed (1st coffee brew-
ing process after appliance switched on), low
amount of liquid (e.g. espresso)
►
Appliance calcified
►
NTC temperature sensor defective
►
NTC temperature sensor not screwed on correctly
►
Logic module defective
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Grinding unit setting not optimum
►
Unsuitable coffee or beans no longer fresh
Remedial action
►
Prewarm cup or rinse out with hot water.
Heat milk
►
Prewarm brewing system; to do this open
and close ground coffee duct flap and start a
coffee brewing process.
►
Press function switch briefly to draw steam
in order to increase the heater temperature.
►
Descale.
►
Replace NTC temperature sensor
►
Tighten NTC temperature sensor
►
Replace logic module
►
Adjust grinding unit setting. (Change degree
of grinding only while the grinding unit is
running)
►
Change coffee or use fresh beans
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