How much does it cost to fix Baxi error code Overheat Lockout?

Typical repair cost for the Baxi Overheat Lockout fault is £100-350 including labour.

Overheat Lockout High

Baxi Overheat Lockout Fault Code

Q: What does the Baxi Overheat Lockout fault code mean?

Your boiler has switched itself off because it has become too hot to operate safely and requires a manual reset once it has cooled down.

Also written as OVERHEATLOCKOUT — same fault.

The Baxi Overheat Lockout fault code means: your boiler has switched itself off because it has become too hot to operate safely and requires a manual reset once it has cooled down.. It appears on 3 Baxi models in our database.

Technical description: Indicator: Upper LED Off, Middle LED Flash, Lower LED Off, Bottom LED Off.

Typical repair cost £100-350 (including labour)

DIY fix possible

Ensure all radiator valves are fully open to allow water to flow.Wait for the boiler to cool down for at least 30 minutes.Turn the selector switch to the 'Reset' position and hold for 5 seconds before turning it back to 'On'.

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Baxi models that show the Overheat Lockout fault code

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

Source

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

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