High Lockout
52 on Ideal Classic FF

Your boiler is failing to keep its small pilot flame burning, which means it cannot fire up to provide heating 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

PILOT WILL NOT STAY LIT WHEN THE GAS VALVE BUTTON IS RELEASED

What causes this fault?

This fault occurs when the boiler's safety monitoring system fails to detect a constant pilot flame, causing it to shut down gas flow for safety. The most common reason is a worn-out thermocouple or a faulty overheat thermostat that is incorrectly sensing that the boiler is getting too hot.

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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