Emergency
20 on Vokera Linea One

Your boiler has detected that it is dangerously overheating or that exhaust fumes are not escaping properly, so it has shut itself down to prevent damage or fire risk.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

high limit thermostat/fume thermostat

From this model's manual
Verified against the Vokera Linea One installation & service manual, page 31.
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 emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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