High
Lockout LED on Potterton Puma 100e

Your boiler has shut itself down as a safety precaution because it has detected an internal fault or an interrupted gas supply.

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

Indicates that the boiler has locked out. The boiler is fitted with several protection devices and operation of any of these will cause the boiler to 'Lockout'.

From this model's manual
Verified against the Potterton Puma 100e installation & service manual.
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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