BoilerFaultCodesYour boiler is failing to ignite or stay lit, meaning you will not have any heating or hot water until the issue is resolved.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler does not light, or lights briefly at the correct burner pressure then goes off
What causes this fault?
This fault occurs when the boiler's control system successfully sends a spark to the burner, but the flame either fails to catch or isn't detected once it has lit. The most common reasons include a worn sensor that can no longer 'see' the flame, a faulty gas valve that isn't releasing fuel, or a build-up of carbon on the ignition components. Because the system cannot confirm a safe, steady flame, it shuts down the boiler for safety.
This fault is more common during the first cold snap of autumn when internal components that have been idle through summer are suddenly required to operate under high demand.
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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