How to replace the wirefuse, control board, steam switch and Jaw - Nespresso EF748, Nespresso EF749 – Coffee machine

General disassembly (stage 1)

Tools:
- Special screwdriver (oval)
General information:
The screws are labelled with letters (A, B and C) in the figures.
These refer to the tightening torques for the screws.
A = 0,5 to 0,9 Nm
B = 0,8 to 1,4 Nm
C = 1,3 to 1,8 Nm
A and B can be tightened by hand (A = tighten lightly, B = tighten firmly).
For tightening screws labelled C it is imperative that a torque wrench is used.
Procedure:
1. Remove water tank, drip tray, and capsule container.
2. Place machine on the disassembly jig (item no. 28087).
3. Remove screws (13) on the underside and rear of the side pieces.
4. Remove side pieces (2 and 3).

General disassembly (stage 2)

Tools
- Torx screwdriver T10, T15
- Special screwdriver (oval)
Procedure
1. General disassembly stage 1.
2. Remove 3 bolts (13) on the cover at the rear (9) on the underside.
3. Open jaw and remove screws (111) on the cover.
4. Unscrew ball (80) on the jaw stick.
5. Remove screws (83) and closing lever (84).
6. Move cover (81) a little to the side and remove.
7. Remove 2 bolts (12) on the cover at the rear on the top.
8. Remove cover at the rear (9).

Replacing fine-wire fuse
Tools:
- Torx screwdriver T15
- Long-nose pliers
- Torque wrench
Procedure:
1. General disassembly stage 1 and 2.
2. Remove all connections with red cable.
3. Undo clamp (43).
4. Replace fault fine-wire fuse (998).
5. Assemble in reverse sequence. Tighten bolt (46) to torque C using torque wrench

Replacing control board
Tools:
- Torx screwdriver T10
- Long-nose pliers

General disassembly stage 1
2. Place earthing strap around the wrist and
connect to the earthing cable on the unplugged machine! In this way a potential
difference is avoided.
3. Remove connections from the board.
4. Undo 2 screws (12) and remove the
control board.
5. Replace control board (59).
6. Assemble in reverse sequence.

Replacing main switch or steam switch

Tools:
- Torx screwdriver T10
- Long-nose pliers
Procedure:
1. General disassembly stage 1
2. Remove screws (12) on underside of appliance.
3. Remove connections
4. Replace main switch (62) or steam switch (63).
5. Assemble in reverse sequence.

Replacing LED

Tools:
- Torx screwdriver T10
Procedure:
1. General disassembly stage 1

2. Remove connector in the electronic mainboard.
3. Remove screws (12) and cover (33).
4. Remove screw (48) on the LED board.
5. Replace LED board (58).
6. Assemble in reverse sequence.

Replacing steam pipe

Tools:
- Torx screwdriver T10
- Torque wrench
Procedure:
1. General disassembly stage 1
2. Remove screws (12).
3. Remove cover (32).
4. Remove steam pipe (40) and replace.
5. Assemble in reverse sequence. Tighten bolt (12) to torque C using torque wrench.

Replacing the jaw

Tools:
- Torx screwdriver T10, T15
- Cross-headed screwdriver
- Long-nose pliers
Procedure:
1. General disassembly stage 1
2. Open jaw and remove screws (111) on the cover.
3. Unscrew ball (80) on the jaw stick (134).
4. Remove screws (83) and closing lever (84).
5. Move cover (81) a little to the side and remove.
6. Disassemble hoses (85, 65) on the ceramic valve and remove grounding wire (115) on the support.
7. Pull off hose (132) on the expansion housing.
8. Unplug heating PTC (110) and reed contact (86) on the control board.
9. Remove screws (131) on the support module (126).
10. Remove complete jaw and replace

Complete jaw disassembly

Tools:
- Hammer (plastic head)
- Drift No. 4
- Torx screwdriver T10
- Torque wrench
Procedure:
1. General disassembly stage 1.
2. Disassemble jaw as per page 27.
3. Remove capsule cage (see page 31)
4. Remove cover (112).
5. Remove springs (98).
6. Remove shafts (108 +127).
7. Remove side closing lever (120), locking lever (119) and shaft (113).
8. Remove screws on the control board.
9. Remove swivelling plate (97) with ejector lever (94) and spring bearing (99).

Replacing reed contact
Perform points 1 to 9
10.Remove screws (87).
11.Remove screws (96) and bearing (109).
12.Remove reed contact (86) and replace.
Attention: The cover on the ceramic valve must not be removed.
13.Assemble in reverse sequence.

Replacing connection to capsule cage
Perform points 1 to 9
10.Remove screws (96) and bearing (109).
11.Remove clamp (45).
12.Replace connection (91) and fit new seal (90).
13.Assemble in reverse sequence.

Replacing ceramic valve
Perform points 1 to 9
10.Remove screws (96) and bearing (109).
11.Remove clamp (45) on the ceramic valve.
12.Remove connection (91) and hose (88).
13.Remove screws (87) on the ceramic valve.
14.Replace complete ceramic valve (incl. reed contact, 86).
15.Assemble in reverse sequence. Fit new seal (90) and tighten screws (87) to torque C using torque wrench.