How much does it cost to fix Worcester Bosch error code 8C?

Typical repair cost for the Worcester Bosch 8C fault is £150-350 including labour.

8C High

Worcester Bosch 8C Fault Code

Q: What does the Worcester Bosch 8C fault code mean?

Your boiler has detected that it is getting too hot too often and has locked itself down as a safety precaution to prevent damage.

The Worcester Bosch 8C fault code means: your boiler has detected that it is getting too hot too often and has locked itself down as a safety precaution to prevent damage.. It appears on 1 Worcester Bosch model in our database.

Technical description: Super-Lock caused by too frequent thermostat overheat detections during burning

Typical repair cost £150-350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Worcester Bosch models that show the 8C fault code

Click a model for the full fault code list and model-specific repair notes.

Greenstar 12i System Repair: £150-350

Source

Worcester Bosch 8C fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026