How much does it cost to fix boiler error code Overheat thermostat lockout?

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

Overheat thermostat lockout High

Boiler Fault Code Overheat thermostat lockout

Also written as OVERHEATTHERMOSTATLOCKOUT — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Overheat thermostat lockout appears across 1 boiler brand and 8 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 switched itself off to prevent damage or danger. (As reported on Ideal Classic FF 330)

Pick your boiler brand for the Overheat thermostat lockout fix

Ideal Overheat thermostat lockout 8 models

Source

Information for the Overheat thermostat lockout fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →

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