High
CONDITION 3 on Keston R-sm 20 FB

Your boiler is trying to start up but the burner refuses to ignite, meaning it cannot produce any heat for your home or water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

The fan motor starts and the burner does not light up

Engineer required

This is a high 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

CONDITION 1View →CONDITION 2View →

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