Vaillant ecoTEC plus VUI Series, Installation And Maintenance Instructions Manual

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Installation and maintenance instructions 0020308121_04
2
1
3
A
B
C
4. Reconnect the plug or, if required, the two plugs to the
fan motor
(2) .
5. Reconnect the two plugs to the gas valve assembly (3) .
6. Screw the union nut onto the gas valve assembly with
a new seal. In the process, secure the gas pipe against
twisting. Tightening torque, see appendix.
7. Open the gas stopcock.
8. Check the product for tightness. (
→
Section 9.17)
9. Check whether the sealing ring is positioned correctly
in the air intake pipe.
10. Plug the air intake pipe (1) onto the intake stub and
push the air intake pipe into the upper retainer, as
shown in the figure.
11. Check the gas connection pressure/gas flow pressure.
(
→
Section 9.13.3)
12. Observe the tightening torques for the screw plug on
the gas valve assembly and on the gas isolation valve,
see appendix.
12.8 Cleaning/checking the components
1. Carry out the preparatory work before
cleaning/checking any of the components.
(
→
Section 12.8.1)
2. Carry out the work required to finish the task
after cleaning/checking any of the components.
(
→
Section 12.8.8)
12.8.1 Preparing the cleaning and inspection work
1. Temporarily decommission the product.
(
→
Section 14.2)
2. If required, remove the installed modules from below
the product (
→
Module installation instructions).
3. Remove the front casing. (
→
Section 7.10.2)
4. Hinge the electronics box downwards.
5. Protect the electronics box against spraying water.
6. Remove the compact thermal module.
(
→
Section 12.7.1)
12.8.2 Cleaning the heat exchanger
1
2
3
1. Never undo the four nuts on the stud bolt or tighten
them.
2. Clean the spiral immersion heater (1) of the heat ex-
changer (3) using a plastic brush and, if required, vin-
egar (up to max. 5% acid content).
–
Cleaning agent reaction time: 20 min
3. Wipe away the loosened dirt with a damp cloth. Ensure
that the insulating mat
(2) on the rear of the heat ex-
changer remains dry.
◁
Moisture may drain out of the heat exchanger via
the condensate siphon.
4. Check the insulating mat on the heat exchanger for
damage.
Result:
Insulating mat damaged
▶
Replace the insulating mat (
→
Spare parts instruc-
tions for the heat exchanger insulating mat).
5. Clean the condensate siphon. (
→
Section 12.8.6)
12.8.3 Checking the burner and burner insulating
mat for damage
3
2
1
1. Check the surface of the burner (2) for damage, such
as hairline cracks, dents or other deformations.
Result:
Burner damaged
▶
Replace the burner flange. (
→
Section 13.7.5)
2. Fit a new burner flange seal (3) .
3. Check the insulating mat (1) on the burner flange for
damage.
Result:
Insulating mat damaged
▶
Replace the burner flange. (
→
Section 13.7.5)