Boiler Fault Code Overheat thermostat trip

Also written as OVERHEATTHERMOSTATTRIP — same fault.

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

Fault code Overheat thermostat trip appears across 1 boiler brand and 5 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has detected that it is getting too hot and has automatically shut down to prevent any damage or safety issues. (As reported on Grant Vortex Eco)