High Lockout
71 on Vokera Easi-Heat 25

Your boiler has detected an internal communication or temperature sensor error that is currently preventing it from running normally.

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

Temporary fault code (Refer to section 7.10)

What causes this fault?

This fault occurs when the boiler's control board fails to receive a consistent signal from the internal temperature sensors. The most common reason is a malfunctioning sensor that provides an incorrect reading, though it can also be caused by a loose wiring connection or a developing fault on the main circuit board.

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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