High
FAIL POINT I / Sensor Fault on Worcester Bosch 24/28CDi II RSF

Your boiler has detected an internal communication problem with its sensors or electrical wiring, causing it to stop operating to ensure your 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

Flashing fast - DHW sensor, CH sensor, gas valve, or harness continuity 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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