BoilerFaultCodesYour boiler started to heat up but the flame went out unexpectedly, causing the system to stop working for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame disappears during operation.
What causes this fault?
This fault occurs when the boiler's control system successfully lights the burner but then loses the signal that a flame is present, leading to an immediate shutdown. The most common reasons include a buildup of carbon on the detection probe, a blockage in the drainage system that causes water to back up into the heat exchanger, or an incorrect mixture of gas and air.
This fault is more frequent during freezing winter spells, as a frozen external condensate pipe can cause water to back up and extinguish the flame.
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 F005 — 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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