High Lockout
E16 on Vokera Pinnacle

Your boiler's main control board has encountered a software or electrical error and is unable to operate the 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

Internal fault (PCB)

What causes this fault?

This fault occurs when the boiler's internal computer experiences a breakdown in communication or a hardware failure on its circuitry. The most common reason is electrical degradation of the components on the board over time, or a sudden power surge that has damaged the delicate microprocessors required to control the boiler safely.

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

E01View →E02View →E15View →

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