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Vitocrossal 300 CU3A 26 to 199 Service
Checking Burner Mesh Assembly and Refractory
Service
Replace the burner mesh assembly if the wire mesh is
damaged.
1. Remove electrodes
A
.
2. Undo four nuts
D
and remove fan with gas valve
C
.
3. Release three nuts
B
and remove burner mesh
assembly
H
.
4. Remove refractory
F
with thermal insulating mat
E
.
5. Remove old burner mesh assembly gasket
G
.
6. Check refractory
F
for damage and replace, if
required.
7. Insert thermal insulating mat
E
and refractory
F
according to the electrode position.
Note: Observe the positioning aid on the refractory.
8. Insert new burner mesh assembly
H
with new
gasket
G
and secure with three nuts.
Torque:
3.7 lb.ft (5 Nm).
9. Fit the fan with the gas valve. Torque: 3.7 lb.ft (5 Nm).
1. Check the electrodes for wear and contamination.
2. Clean the electrodes with a small brush (not with a
wire brush) or sandpaper.
3. Check the electrode gaps. If the gaps are not as
specified or the electrodes are damaged, replace
and align the electrodes together with new gaskets.
Tighten the electrode fixing screws with a torque of
2.2 lb.ft (3.0 Nm).
Legend
A
Ignition electrodes
B
Ionization electrode
C
Up to 35 kW (125 MBH)
D
From 45 kW (160 MBH)
CAUTION
Do not damage wire gauze of the burner head.
Checking and Adjust the Ignition and Ionization Electrodes