BoilerFaultCodesYour boiler was working but the flame has unexpectedly gone out, causing the system to stop for safety reasons.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Loss of flame during operation
What causes this fault?
This fault occurs when the boiler successfully lights but cannot maintain a stable flame, causing the system to shut down for safety. It is often caused by a worn-out sensing probe that can no longer detect the fire, or a problematic gas valve that isn't providing a steady fuel supply to the burner.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E128 — 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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