Vaillant ecoTEC plus VU GB 5-5 Series Installation And Maintenance Instructions Manual page 35

7. After installing the new gas valve assembly, carry out a
leak-tightness test (→ Page 24), and set the gas setting
(→ Page 22).
10.10.2 Replacing the burner
1
2
3
4
1. Remove the gas-air mixture unit. (→ Page 29)
2. Remove the ignition and monitoring electrode.
3. Remove the seal (4) from the burner door.
4. Undo the four nuts (1) that are used to secure the insu-
lating mat.
5. Remove the insulating mat (2).
6. Undo the nuts (3) on the burner.
Note
Use a suitable socket spanner (with exten-
sion) to ensure that the burner mat does not
become damaged. You must not use burners
that have a damaged mat.
7. Remove the burner. When doing so, hold the fan and
the burner door securely.
8. Fit the new burner with a new seal.
9. Use all of the nuts and washers (3) to secure the
burner.
–
Torque: 4 Nm
10. Use four nuts (1) to secure the insulating mat. Ensure
that the insulating mat is touching the burner door and
the cut-outs for the insulating mat lie above the cut-outs
for the burner door.
–
Torque: 6 Nm
11. Install the ignition and monitoring electrodes. Use new
seals for this.
0020134823_07 ecoTEC plus Installation and maintenance instructions
–
Torque: 2.8 Nm
12. Install the gas-air mixture unit. (→ Page 32)
13. Check that the product functions correctly and check
the leak-tightness (→ Page 24).
10.10.3 Replacing the insulating mat
If the safety cut-out on the burner door has been triggered,
the insulating mat between the burner door and burner room
may be damaged.
▶
Check and replace the insulating mat.
Note
To replace the insulating mat, proceed in the
same way as when removing the burner. It is
not necessary to remove the burner.
10.10.4 Replacing the fan
1. Remove the gas-air mixture unit. (→ Page 29)
2. Undo the four nuts (1) on the fan.
3. Install the new fan on the burner door in the same ori-
entation in which it was previously positioned.
Condition: Applies for 80 kW and 100 kW
–
Torque: 3.5 Nm
Condition: Applies for 120 kW
–
Torque: 6 Nm
Note
Tighten the screws on the fan evenly. The
fan must not be at an angle.
10.10.5 Replacing the heat exchanger
1. Drain the product. (→ Page 33)
2. Remove the gas-air mixture unit. (→ Page 29)
3. Unscrew the flow and return line in the front area of the
underside of the product.
Troubleshooting 10
1
35