High Lockout
05 on Vokera Linea Max

Your boiler's internal computer has developed a fault and is unable to communicate correctly with the rest of the system.

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

Heating thermistor fault (Open or Short circuit)

What causes this fault?

This fault occurs when the boiler's central control board suffers an internal hardware failure or a memory corruption. It is usually caused by electrical wear and tear over time or a sudden power surge that damages the delicate circuits responsible for managing the boiler's functions.

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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