Micron 120FF. It goes through starting sequence, the igniter lights the pilot, neons 1 to 3 light up but the igniter keeps firing, the pilot is still alight but the main burner doesn't light.
When I remove the cover from the boiler then the main burner lights and neon 4 lights - the boiler appears to run normally.
Does anyone have any suggestions for diagnosing the problem. The fault chart suggests the PCB but as the burner lights OK when the front cover is removed it seems unlikely to be an electrical fault - more likely something to to with a pressure switch or similar.
TIA
When I remove the cover from the boiler then the main burner lights and neon 4 lights - the boiler appears to run normally.
Does anyone have any suggestions for diagnosing the problem. The fault chart suggests the PCB but as the burner lights OK when the front cover is removed it seems unlikely to be an electrical fault - more likely something to to with a pressure switch or similar.
TIA
