Grant Vortex 50/90 - Burner Maintenance and Cleaning

36
Grant Vortex External Module
9 - BOILER SERVICING
Fig. 29
4 ± 0.3 mm
3 to 3.5 mm
Clamp screw
Cleaning the burner
9.4
50/70, 70/90, 90/120 and 120/155 - See Section 13
1 Combustion head - Loosen the two screws
securing the combustion head and withdraw the
head. Clean and refit the combustion head.
2 Inspect the ignition electrodes - Remove the
combustion head.
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 3 to
3.5 mm in front of the nozzle, see Fig 29.
3 Nozzle - The nozzle should be replaced on an
annual service - Check that the nozzle size and type
are correct, refer to table in Section 3.3 and boiler
data label.
With the combustion head removed, loosen the
electrode assembly clamp screw and slide the
electrodes away from the nozzle.
Do NOT attempt to clean 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. 29.
155/200 or 200/240 models - See Section 13.2 and Fig. 30
1 Combustion head - Loosen the two screws
securing the combustion head (NOT the screws in
the slotted ring, Fig. 32) and withdraw the head.
Clean and refit the combustion head.
2 Inspect the ignition electrodes - Remove the
combustion head.
Loosen the electrode clamp screw, disconnect the
leads and withdraw the electrode assembly. Wipe
clean and check for any cracks in the ceramic
insulation. Replace if necessary.
3 Check the electrode and diffuser settings - Fig. 31
To adjust the diffuser disc: Loosen the diffuser clamp
screw and slide the disc along the nozzle holder to
achieve the gap 'A' in Fig. 31, tighten the screw.
To adjust the electrodes: Loosen the electrode
clamp screw and move the electrode unit to achieve
the gap 'B' in Fig. 31, tighten the screw.
Fig. 30
Combustion
head
Combustion head
fixing screw
Electrode clamp
screw
Electrode
leads
Nozzle
holder
Diffuser clamp
screw
Burner
flange
Fig. 31
A
B
Electrode clamp screw
5.75
0
-0.2
3
+0.5
0
Diffuser clamp screw
4.0
+0.5
7.5
+0.7
- 0.5
_
B
A
Diffuser disc
4 The combustion head position is adjustable on the
155/200 and 200/240 burners. Check that it is fully
closed (position 0), or the 4th line if the 200/240
has been set to maximum output (70 kW).
To adjust the head setting, refer to Fig. 32 and
proceed as follows: Loosen the two screws in the
slotted ring - NOT the two fixing screws, and turn
the blast tube until '0' lines up with the edge of the
slotted ring. Tighten the two screws.