High Lockout
78 on Vokera Easi-Heat 29

Your boiler has detected a temporary internal communication error or a sensor synchronization issue that is preventing it from running properly.

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 internal control board loses track of the temperature readings because the signals from the sensors are inconsistent or mismatched. It is often caused by a failing hot water sensor sending incorrect data or a minor electronic glitch on the main circuit board that prevents the components from communicating correctly.

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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