Emergency
L6 on Keston Combi C30

Your boiler is detecting a flame when there shouldn't be one, so it has shut down for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Flame On Before Gas Valve On

From this model's manual
Verified against the Keston/Keston Combi C30 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

L2View →F2View →

All 25 fault codes on the Combi C30

Seeing a different code? Every code this model can display, in one place.

F1F2F3F4F5F6Fan FaultFlame LossFlame On Before Gas OnFlow Thermistor FaultFlow/Return ReversedHigh Mains VoltageIgnition LockoutL1L2Low Mains VoltageOutside Sensor FaultOverheat LockoutPCB FaultReturn Thermistor FaultRoom Stat FaultSpare PCB Not SetToo Many RestartsWater Pressure

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