High Lockout
Red LED Flashing on Vokera Option

Your boiler has detected a safety issue and has shut down to protect your home, which means you currently have no heating or hot water until it is reset or repaired.

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.

Technical description

Lockout fault (Reset required)

What causes this fault?

This fault occurs when the boiler fails to light or loses its flame three times in a row, causing it to stop for safety reasons. The most common reasons include a lack of gas supply, a build-up of carbon on the ignition probe, or a component failure that prevents the burner from firing up correctly.

This issue is more frequent during the first cold snap of autumn when a boiler is turned back on after months of inactivity, often due to a stuck gas valve or debris in the system.

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.

Find a Gas Safe engineer
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