High Lockout
A8 on Worcester Bosch WR325 RSF

Your boiler has lost its internal connection between the main control board and the display panel, meaning it cannot communicate with itself properly.

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

Break in communication

What causes this fault?

This fault occurs when the boiler's internal computer brain loses its physical connection to the front display panel. It is usually caused by a loose or damaged ribbon cable, or a component failure on the main circuit board that prevents data from traveling between the two parts. Because they cannot 'talk' to each other, the boiler shuts down for safety.

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

A7View →B1View →C6View →

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