High Lockout
660 on Worcester Bosch WR325 RSF

Your boiler has detected an electrical fault within its internal wiring or a control component, causing it to shut down for safety.

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

Short circuiting

What causes this fault?

This fault occurs when an electrical current follows an unintended path within the boiler's circuitry, often due to a component failure or damaged insulation. The most common reasons are water leaking onto internal electrical parts or a critical failure within the main control board's surface components.

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

E5View →EAView →FDView →

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