BoilerFaultCodesTechnical description
Error during start-up procedure (requires 3 minute venting cycle after resolution)
What causes this fault?
This fault occurs when the boiler tries to light but fails to establish or sense a stable flame within the set time limit. The most common reasons include a lack of gas reaching the burner, worn-out ignition components that can no longer create a spark, or a dirty sensor that cannot tell the boiler the flame is safely lit.
This issue sometimes surfaces during the first cold snap of autumn when internal components that have been idle all summer finally fail under the strain of constant use.
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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