Technical information

Combi 70 & Combi 90 Oil Boilers

Fig. 34 - Combi 90 baffle positions

8 - BOILER SERVICING

Cleaning the burner

8.4

Fig. 35 (Combi 90 shown)

IMPORTANT: The electrode settings given above

MUST be observed

4 ± 0.3 mm

2 to 2.5 mm (Combi 70)

3 to 3.5 mm (Combi 90)

Clamp screw

See section 12.1

1 Combustion head - Loosen the two screws

securing the combustion head to the burner flange

and withdraw the head. Clean and replace the

combustion head.

2 Inspect the ignition electrodes - With the combustion

head removed, loosen the electrode clamp screw and

withdraw the electrode assembly. Wipe clean and

check for any cracks in the ceramic insulation. Replace

if necessary.

Check the electrode settings - Electrode tips

approximately 4 mm apart and 2 to 2.5 mm

(Combi 70) or 3 to 3.5 mm (Combi 90) in front

of the nozzle, see Fig 35.

3 Nozzle - Check that the nozzle size and type are

correct, refer to tables in sections 2.2 or 2.3 and

boiler data label. Clean the nozzle with Kerosene if

necessary. Do not use a pin or piece of wire to

clean the nozzle.

Replace the nozzle if a build up of carbon is

present.

With the combustion head removed, loosen the

electrode assembly clamp screw and slide the

electrodes away from the nozzle. Remove the

nozzle using a good fitting spanner (16 mm). The

use of an ill-fitting spanner will damage the nozzle

and could lead to an incorrect flame pattern.

Always check the electrode settings after replacing

the nozzle, see Fig. 35.