High Lockout
E15 on Vokera Pinnacle

Your boiler's main internal computer has developed a fault and is no longer able to 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

Internal fault (PCB)

What causes this fault?

This fault occurs when the boiler's main control board suffers an internal electronic failure or a loss of communication between components. It is often caused by the natural aging of electrical capacitors or damage from an unexpected power surge in the home's electricity supply.

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

E10View →E11View →E16View →

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