Checking Burner Mesh Assembly And Refractory; Placing The Burner Door In The Service Retainer; Check And Adjust Ignition And Ionization Electrodes - Viessmann Vitocrossal 300 Service Manual

Service

Checking Burner Mesh Assembly and Refractory

Checking and Adjust the Ignition and Ionization Electrodes
Legend
A Ignition electrodes
B Ionization electrode
C Up to 35 kW
D From 45 kW
20
Vitocrossal 300 CU3A 26 to 57 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 lbf.ft (5 Nm).
9. Fit the fan with the gas valve. Torque: 3.7 lbf.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.
CAUTION
Do not damage wire gauze of the burner head.
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
1.8 lbf.ft (2.5 Nm).