Nespresso EF 474 Coffeemaker User Manual


 
16
Troubleshooting
Service Manual EF 473 / EF 474 enVersion 1.0
4 Press On/Off button to perform
automatic self test - continued
4.1 Machine is not working (no function)
- continued
YES - g) Check if electrical wires are functional
YES - Replace electronic mainboard
NO - Replace defective(s) wire(s)
NO - Go to point 4.2
4.2 Backlighted coffee button blinks at irregular
intervals
YES - Check if thermoblock heating element is func-
tional
YES - Replace NTC
NO - Replace thermoblock
NO - Self test ok. Go to point 5
5 Check coffee temperature while
preparing a coffee (see page 30)
5.1 No coffee outlet
YES - a) Water circuit is empty
YES - Fill water circuit (see page 9)
NO - Go to point b)
YES - b) Flow meter is clogged
YES - Clean or replace it
NO - Go to point c)
YES - c) Pyramid plate is clogged
YES - Replace CBU
NO - Go to point d)
YES - d) Machine is blocked by scale YES - Descale machine (see page 25)
NO - Go to point 5.2
5.2 Temperature is too low (less than 83°C)
YES - Descale the machine (see page 25)
NO - Go to point 5.3
5.3 Temperature is too high (more than 89°C)
YES - Change NTC
NO - Go to point 6
6 Check for leaks and check flow
rate (see pages 27, 28 and 29)
6.1 Leakage at extraction system
YES - Replace CBU
NO - Go to point 6.2
6.2 Leakage at tubes connection
YES - Replace defective tube and seal
NO - Go to point 6.3
6.3 Flow rate out of range
YES - Machine is scaled
YES - Descale machine (see page 25)
NO - Replace pump
NO - No trouble found during the check procedure.
Contact Nespresso Technical Correspondant for
further details in order to take decision.
7 Descaling process (if needed) 7.1 Machine scaled
YES - Descale machine (see page 25)
NO - Go to point 8
8 Final cleaning (see page 31)
End of check procedure
Check procedure Symptoms Action / repair work Further action / repair work