Boiler at lock out High

Potterton Boiler at lock out Fault Code

Also written as BOILERATLOCKOUT — same fault.

The Potterton Boiler at lock out fault code means: your boiler has stopped working as a safety precaution and needs to be manually restarted to see if it can clear the internal error.. It appears on 1 Potterton model 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: Light on - Reset
Typical repair cost £120-300 (including labour)

DIY fix possible

Locate the reset button on the front control panelPress and hold the reset button for 3-5 secondsWait a few minutes to see if the burner ignites; if it locks out again immediately, stop and call a professional

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Potterton models that show the Boiler at lock out fault code

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

Source

Potterton Boiler at lock out fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.

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