OVERHEAT LOCKOUT INDICATOR High

Halstead OVERHEAT LOCKOUT INDICATOR Fault Code

Also written as OVERHEATLOCKOUTINDICATOR — same fault.

The Halstead OVERHEAT LOCKOUT INDICATOR fault code means: your boiler has switched itself off because it got too hot, which is a safety feature designed to prevent overheating damage.. It appears on 8 Halstead models in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Indicator illuminates when the overheat cut off device has operated; requires inspection of the overheat cut off device and potentially a manual reset via the ignition reset button.
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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Halstead models that show the OVERHEAT LOCKOUT INDICATOR fault code

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

Source

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

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