High Lockout
AL52 on Vokera Mynute Vhe

Your boiler has encountered a internal electronic communication error that is preventing it from running 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

Internal fault

What causes this fault?

This fault occurs when the boiler's internal computer chips lose the ability to speak to one another, effectively causing a 'brain freeze' within the system. The most common reason is a hardware failure on the main circuit board, where an electrical component has worn out or short-circuited.

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

AL55View →

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