High Lockout
E05 on Vokera Pinnacle

Your boiler's main internal computer has developed a malfunction and can no longer control the heating 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

Heating flow sensor NTC fault

What causes this fault?

This fault occurs when the boiler's main control board suffers a hardware failure and can no longer process data or send signals to other components. It is often caused by an electrical surge or the natural degradation of the solder joints and capacitors on the circuit board over time. Because the board acts as the brain of the system, the boiler stops immediately to prevent unpredictable or unsafe operation.

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

E02View →E07View →E11View →

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