High Lockout
LE on Ideal Classic FF

Your boiler’s internal computer has encountered a critical failure and can no longer control the heating system safely.

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

BOARD ERROR

What causes this fault?

This fault occurs when the boiler's main control board suffers an internal electrical failure or memory corruption. The most common reasons are age-related wear to the board's capacitors or a sudden power surge that has damaged the delicate circuitry responsible for managing the boiler's safety sequences.

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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