High Lockout
E08 on Vokera Pinnacle

Your boiler's internal temperature sensors have developed a fault, meaning the system cannot safely monitor the water temperature and has shut down as a precaution.

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 PCB fault

What causes this fault?

This fault occurs when the boiler's internal temperature sensors stop providing a reliable reading to the control board. The most common reason is that the thermistor has physically degraded or developed an electrical short, though it can also be caused by loose wiring connections between the sensor and the main computer. Because the boiler no longer knows how hot the water is, it shuts down to prevent the unit from overheating.

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

E07View →E09View →E05View →

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