High Lockout
HE on Ideal Mexico HE

Your boiler's internal computer has encountered a critical electronic failure and can no longer control the heating process 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 electronic failure or loses communication with its sensors. The most common reason is age-related wear on the electrical components or a sudden power surge that has damaged the delicate circuitry. Because the board can no longer safely monitor the flame or water temperature, it shuts the system down as a safety precaution.

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

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