Spark Electrode; Burner; Combustion Chamber And Heat Exchanger - Vaillant ecoMAX pro 18E Instructions For Use Installation And Servicing

14 Servicing

14.4 Spark Electrode

Disconnect the ignition lead and earth lead from the
igniter unit and two securing screws at the spark
electrode. Withdraw the spark electrode carefully from
the combustion chamber, see fig 14.4.
Inspect the tips for damage.
Clean away any debris and check the spark gap is
3.5 to 4.5 mm.
Check the electrode gasket for signs of damage and
replace if necessary.

14.5 Burner

Note!
If the functional checks did not indicate poor
combustion then it is not necessary to service
the burner.
Caution!
The burner door seal and combustion
chamber burner door securing nuts on the
burner module, see figs 14.6 and 14.7 must
be replaced each time the module is removed
for example during maintenance if the burner
flange insulation shows any signs of damage or
small cracks it must also be replaced.
Isolate the gas supply at the gas service cock.
Disconnect the gas supply at the gas service cock.
Note!
Do not disconnect at the gas valve.
Remove the two gas pipe bracket securing
screws from underside of inner case,
see fig 14.5.
Drop down the electronics box into the
service position.
Remove the four screws from the chassis front,
see fig 14.2.
Remove the chassis front by pulling it out at
the top from its retaining slots.
Note!
When replacing chassis front panel ensure the
bottom fits behind lip.
Disconnect the gas valve electrical plug at the gas valve.
Disconnect the electrical leads from the fan.
Remove the five combustion chamber burner door
securing nuts, these should be discarded and replaced
with the new nyloc nuts supplied in the burner door seal
kit.
Gently remove the fan, gas valve and burner assembly
from the combustion chamber complete with the gas
pipe bracket and seal, see fig 14.6.
Clean the burner with a soft brush taking great care not
to damage the front insulation. DO NOT use wire or
sharp instruments to clean the holes of the burner.
Inspect the burner for any signs of damage.
28
Remove and discard the burner door seal and replace
with new, see fig 14.7.
Removal of the burner is not necessary during a normal
service.
Note!
If the burner has to be removed it will require a
new gasket when refitted, see diagram 14.8.
Note!
When replacing ensure that the sealing
grommet, situated below the gas valve is
correctly re-seated.

14.6 Combustion chamber and heat exchanger

Refer to fig 14.9.
Remove loose debris from combustion chamber using
a soft brush and vacuum cleaner. Carefully flush any
remaining debris through the condensate trap (ensure
the water is kept away from electrical components).
Instructions for Use, Installation and Servicing ecoMAX pro
Fig 14.4
Fig 14.5