Furnace locks out with E02 during ignition sequence, fan runs but no flame established.

Safety warning: Gas components must only be worked on by a qualified gas engineer. Do not remove the combustion cover or touch the gas valve if you are not certified.

User-level checks:

• Confirm that the gas isolation valve to the furnace is fully open.
• Check that other gas appliances (hob, boiler, etc.) operate normally. If they do not, contact your gas supplier.
• Power-cycle the furnace: switch off at the fused spur for 30 seconds, then back on and attempt a reset.

Technician checks:

• Measure inlet and outlet gas pressures at the Ravenheat gas valve test points while the unit calls for heat.
• Check gas valve coil resistance and verify 230V (or specified) supply from the PCB during ignition.
• Inspect and clean any internal gas valve filter if fitted, following Ravenheat service instructions.
• Confirm correct earthing and polarity to the appliance, as incorrect polarity can prevent valve operation.

If E02 persists after confirming adequate gas supply and electrical feed, the gas valve assembly will typically need replacement and full safety checks.