High
Overheat LOCKOUT on Potterton Suprima HE

Your boiler has detected that it has become too hot and has automatically shut itself down to prevent internal damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Manual reset. The 'Lockout' (Red) light will flash. Occurs if an overheat condition occurs or the overheat stat is off.

From this model's manual
Verified against the Potterton Suprima He System installation & service manual, page 25.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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