Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Unplug electrode from HT lead
Observation:
Thoroughly check the electrode and lead for signs of damage, cracked ceramic insulation, good general condition and cleanliness. Check the spark gap is 2.5 - 4.5mm
Measure the resistance across the electrode, expect continuity / zero resistance.
Refit electrode after test.
Also check the electrode is straight and the correct distance from the burner, if in doubt measure the gap as shown. It should be approximately 19mm from the burner edge.
Measure the resistance across the electrode, expect continuity / zero resistance.
Refit electrode after test.
Also check the electrode is straight and the correct distance from the burner, if in doubt measure the gap as shown. It should be approximately 19mm from the burner edge.
Isolate as per TOPs P4
and refit as necessary