High Lockout
E2222 on Worcester Bosch CDi Classic

Your boiler has detected an electrical fault with the internal sensor that monitors the temperature of the water leaving the unit, preventing it from heating up safely.

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

Flow temperature sensor shorted

What causes this fault?

This fault occurs when the electrical resistance in the flow sensor drops to zero, usually because the component has failed internally or the protective casing has perished. The most common reason is standard wear and tear over several years, though it can also be caused by water leaking onto the electrical connections or a trapped wire in the internal harness.

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

E2 233View →

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