OVERHEAT PROTECTION TEST Emergency

Worcester Bosch OVERHEAT PROTECTION TEST Fault Code

Also written as OVERHEATPROTECTIONTEST — same fault.

The Worcester Bosch OVERHEAT PROTECTION TEST fault code means: your boiler has failed a safety check because it is unable to automatically shut off the burner if the water temperature gets dangerously high.. It appears on 1 Worcester Bosch model in our database.

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description: Burner fails to shut down if the Gas-to-Water heat exchanger water exceeds 100°C. Replace system overheat thermostat.
Typical repair cost £120-190 (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 OVERHEAT PROTECTION TEST fault code

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

Source

Worcester Bosch OVERHEAT PROTECTION TEST 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