High
FAIL POINT I on Worcester Bosch 28 RSF

Your boiler has detected an issue with its internal sensors or electrical connections, which has caused it to stop working to avoid potential damage.

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

Sensor Fault: ST16 connector loose, DHW sensor resistance/continuity fault (yellow wires), CH sensor resistance/continuity fault (red wires), or gas valve solenoid resistance fault.

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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