BoilerFaultCodesYour boiler has detected an unsafe level of carbon monoxide or improper combustion, which means it has shut down to protect your safety.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like E094 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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