High Lockout
F14 on Ideal Logic Max Combi

Your boiler has detected that the electricity supply coming into your home is at a dangerously high voltage, which could damage the internal electronics.

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

High Mains Voltage: Contact electricity provider

What causes this fault?

This fault occurs when the boiler's internal sensors detect that the incoming electrical supply from the national grid has exceeded safe operating limits. While it can sometimes be a sign of a faulty control board, it is usually caused by an external surge or a problem with the local power infrastructure in your street. The boiler shuts down as a safety precaution to prevent the high voltage from frying its sensitive electronic components.

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

F15View →L2View →

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