How much does it cost to fix Grant error code Overheat thermostat trip?

Typical repair cost for the Grant Overheat thermostat trip fault is £120-250 including labour.

Overheat thermostat trip High

Grant Overheat thermostat trip Fault Code

Q: What does the Grant Overheat thermostat trip fault code mean?

Your boiler has detected that it is getting too hot and has automatically shut down to prevent any damage or safety issues.

Also written as OVERHEATTHERMOSTATTRIP — same fault.

The Grant Overheat thermostat trip fault code means: your boiler has detected that it is getting too hot and has automatically shut down to prevent any damage or safety issues.. It appears on 5 Grant models in our database.

Technical description: Boiler will not start/Boiler operating on overheat thermostat. Check the boiler and overheat thermostat; reset if necessary.

Typical repair cost £120-250 (including labour)

Engineer required

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

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Grant models that show the Overheat thermostat trip fault code

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

Source

Grant Overheat thermostat trip fault code information on this page is sourced and cross-checked against the official Grant service / installation manuals for each affected model.

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