High
FAIL POINT I Sensor Fault on Worcester Bosch Greenstar Si

Your boiler has lost the ability to read the temperature correctly, which is preventing it from heating your water or home 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

Sensor Fault. Multiway connector ST16 loose, DHW sensor failure (1kohm to 30kohm range), or CH sensor failure (1kohm to 30kohm range).

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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