Emergency Lockout
E085 on Vokera Evolve

Your boiler has detected an unsafe level of carbon monoxide or improper combustion, which means it has shut down to protect your safety.

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.

Technical description

Combustion fault/high CO

What causes this fault?

This fault occurs when the boiler's internal sensors detect that the fuel is not burning safely or that dangerous carbon monoxide levels are present within the unit. The most common reasons include a failing gas valve that isn't regulation pressure correctly or worn-out ignition components that are preventing a clean flame.

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.

Find a Gas Safe engineer
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Related fault codes

E077View →E091View →

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