Stovax PR0919 - Manual (Page 28)

28
SERVICING INSTRUCTIONS
REPLACING PARTS
8. PILOT UNIT ASSEMBLY
8.1 The pilot assembly consists of four components which can
be individually changed:
1. Pilot burner bracket
2. Pilot injector
3. Electrode
4. Thermocouple
Before commencing work on the pilot the Main Control
Assembly must be removed, see Section 7 above.
8.2 Pilot Burner Bracket
• Remove the electrode, see paragraph 8.3
• Remove the thermocouple, see paragraph 8.5
• Remove the pilot pipe
• Remove the two screwed securing the bracket
The pilot burner bracket can now be removed.
• Replace in reverse order
• Check the pilot gasket and if damaged, replace with a
new one
8.3 Electrode
• Pull the ignition lead off the electrode and undo the
retaining nut, Diagram 15
15
AR1349
• Replace with a new electrode. Do not over-tighten the
nut; this could break the component
• Replace the ignition lead
16
AR1874
A
B
8.4 Pilot Injector
• Undo the pilot pipe from the gas valve and from the
underside of the pilot burner, Diagram 16
• Remove the pipe and the injector drops out from the
burner
8.5 Thermocouple
• Disconnect the thermocouple from the gas
valve/interrupter, Diagram 16, Arrow B
• Undo the thermocouple nut in the back of the pilot
bracket half a turn. This releases the thermocouple.
When replacing with a new thermocouple, take care to
bend the new component to the same shape as the
thermocouple just removed.
To refit the thermocouple into the pilot bracket, ensure it is
pushed fully into the hole. There is a stop on the
thermocouple to set the height.
• Lock the retaining nut just enough to grip the
thermocouple
• Connect the thermocouple to the valve/interrupter and
take care not to over-tighten
9. IGNITION LEAD
17
AR1872
9.1 To replace the ignition lead:
• Release the Main Control Assembly and tilt backwards,
see Section 7 above
• Remove the ignition lead from the control box, Diagram
17
• Remove the ignition lead from the electrode, Diagram 17
Note the direction of the lead. The new lead must follow
exactly the same route.
NOTE: THE IGNITION LEAD MUST NOT PASS IN
FRONT OF THE CONTROL BOX AS THIS CAN DAMAGE
THE SENSITIVE ELECTRONICS.