Vaillant ecoTEC plus Installation And Maintenance Instructions Manual page 43

5
4
3
1. Remove the air intake pipe.
2. Remove the three plugs from the gas valve assembly
(2).
3. Remove the plug from the sensor on the Venturi (1) by
pushing in the latching lug.
4. Unscrew the two union nuts (5) and (4) on the gas valve
assembly. Use an open-ended spanner to counterhold
the opposite side of the gas valve assembly (4) and (5)
when unscrewing.
5. Either remove the unit comprising the fan with gas valve
assembly (Replacing the fan (→ Page 42)), or use an
offset screwdriver or Torx T20 socket to unscrew the
fixing screw of gas valve assembly (3) from the retainer.
Note
The screw in the gas valve assembly retainer
secures the gas valve assembly against turn-
ing and must be screwed back in once the
gas valve assembly has been replaced.
6. Remove the gas valve assembly from the retainer.
7. Reinstall the new gas valve assembly in the reverse
order. Use new seals for this.
8. When tightening the union nuts on the gas valve as-
sembly, use an open-ended spanner to counterhold the
opposite side of the gas valve assembly (4) and (5).
9. After installing the new gas valve assembly, perform
a leak-tightness test (→ Page 34), gas family check
(→ Page 29) and gas setting (→ Page 31).
0020244998_04 ecoTEC plus Installation and maintenance instructions
13.6.4 Replacing the Venturi
1
2
1. Remove the air intake pipe.
2. Remove the plug from the sensor on the Venturi (1) by
pushing in the latching lug.
3. Unscrew the union nuts (3) of the gas connection pipe
(2) on the gas valve assembly.
4. Remove the Venturi, including the gas connection pipe,
from the fan by turning the bayonet fitting on the Venturi
anti-clockwise as far as it goes and removing it straight
from the fan.
7
6
5
4
5. Remove the gas connection pipe (1) from the Venturi
(3) by removing the clamp (4) and pulling the gas con-
nection pipe out vertically. Dispose of the seal (7).
6. Pull the gas injector (6) straight off, and keep it for re-
use.
7. Check whether the Venturi is free of residue at the gas
inlet side.
Caution.
Risk of material damage to the product.
Lubricant can block function-related channels
in the Venturi.
▶
Do not use lubricant when installing the
gas restrictor.
8. Ensure that you use the correct gas injector (colour
coding and position of pins on the underside of the gas
injector). The colour of the gas injector must match the
colour of the coding resistor on the PCB.
1
2
3
1
2
3
43