High Lockout
23 on Potterton Performa 28i

Your boiler is failing to light the fuel or keep the burner running, meaning it is not producing any heat or hot 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

Flame Failure

What causes this fault?

This fault occurs when the boiler attempts to light the burner but cannot detect a stable flame. The most common reasons include a worn-out sensor that can no longer 'see' the fire, a blockage in the gas supply, or an electronic failure that prevents the initial spark from occurring.

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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