How much does it cost to fix Johnson Starley error code OVERHEAT LOCKOUT?

Typical repair cost for the Johnson Starley OVERHEAT LOCKOUT fault is £120-280 including labour.

OVERHEAT LOCKOUT High

Johnson Starley OVERHEAT LOCKOUT Fault Code

Q: What does the Johnson Starley OVERHEAT LOCKOUT fault code mean?

Your boiler has switched itself off because it became too hot, acting as a safety measure to protect the internal components.

Also written as OVERHEATLOCKOUT — same fault.

The Johnson Starley OVERHEAT LOCKOUT fault code means: your boiler has switched itself off because it became too hot, acting as a safety measure to protect the internal components.. It appears on 1 Johnson Starley model in our database.

Technical description: Should a fault occur, the heater will shut down and these blocking codes will be displayed.

Typical repair cost £120-280 (including labour)

DIY fix possible

Wait at least 15 minutes for the unit to cool down completely.Check that all internal registers and warm air vents are open and not blocked by furniture.Press the 'Reset' button on the control panel to see if the heater restarts.

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Johnson Starley models that show the OVERHEAT LOCKOUT fault code

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

J32 System ET Repair: £120-280

Source

Johnson Starley OVERHEAT LOCKOUT fault code information on this page is sourced and cross-checked against the official Johnson Starley service / installation manuals for each affected model.

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