SERVICING INSTRUCTIONS

REPLACING PARTS

8.PILOT UNIT ASSEMBLY

8.1The 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.

8.2Pilot 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

8.3Electrode

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

A

B

AR1874

8.4Pilot 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

8.5Thermocouple

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

9.1To 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.

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Stovax PR0919 manual Pilot Unit Assembly, Ignition Lead