BoilerFaultCodesYour boiler is starting up but struggling to keep the flame alight, causing it to shut down for safety purposes.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Frequent loss of flame (safety error )
What causes this fault?
This fault occurs when the boiler's internal sensors lose track of the flame shortly after ignition, leading the system to shut down for safety. It is typically caused by a worn-out sensing probe that can no longer 'see' the fire, or a faulty gas valve that isn't providing a steady enough flow of fuel to keep the burner lit. In some cases, a build-up of carbon or debris on the burner can also prevent the flame from staying stable.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like E129 — 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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