High Lockout
08 on Vokera Synergy E

Your boiler has shut down because a safety sensor detected that a internal component has become too hot.

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

Appears if the burner thermostat has been activated.

What causes this fault?

This fault occurs when a safety sensor near the burner detects that the internal temperature has exceeded safe limits, causing the boiler to shut down to prevent damage. The most common reason is a build-up of debris or limescale inside the heat exchanger which restricts water flow, but it can also be caused by a faulty sensor or a pump failure.

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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