10.0 Servicing the Boiler
27
10.1
Annual Servicing
(Continued)
15. Gently clean the heat exchanger with a soft
brush, taking care not to damage any of the fins.
16. Inspect the side insulation pieces and replace
if they are damaged or deteriorated in any way
and brush out any debris or deposits from the
combustion box. Do not allow any foreign matter
to enter the gas valve pressure sensor on the
combustion box base.
17. Undo the screws securing the injector
manifold to the burner assembly and remove the
manifold. Examine the injectors for blockage,
cleaning as necessary. Do not use hard tools,
such as pins or wire (Fig. 47).
18. Clean the burner with a soft brush taking care
not to damage the electrodes. Check the
condition, positions and gaps of the electrodes.
19. The pressure reducing valve should not
require any maintenance on an annual basis, but
if problems are experienced with pressure the
cartridge should be cleaned.
Cleaning The Cartridge
20. Turn off the mains water supply. Unscrew the
cartridge from the the valve body and rinse
thoroughly in clean water (Fig. 48).
21. Check the primary system pressure vessel
charge and system pressure, and the d.h.w.
pressure vessel charge. Repressurise as
necessary.
22. Turn the heads of the temperature/pressure
relief valve, the d.h.w. pressure relief valve and
primary system pressure relief valve
NOT MORE
THAN
1
/
4
TURN
to ensure that they will open and
reseat, and that any discharge pipework is clear.
NOTE:
To test the valves as described above
it is not necessary to turn the relief valve head
“over centre” past the return cam.
23. Reassemble in reverse order of dismantling
and recommission.
24. Complete the relevant section of the
“Benchmark” Installation, Commissioning and
Service Record Log Book and hand it back to the
user.
Burner
Spark Electrode
Sensing Electrode
Securing Screw
Securing Screw
Injector
Injector Manifold
Gas Supply
Sealing Washer
Reducing Valve
Reducing Valve Cartridge
Fig. 47
Fig. 48
