BoilerFaultCodesYour boiler has lost its flame suddenly while it was running, causing it to stop 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: All Boilers
What causes this fault?
This fault occurs when the boiler's internal monitoring system suddenly loses track of the flame while it should be burning. The most common reasons are a dirty or worn-out sensor that can no longer 'see' the fire, or an unstable gas supply that causes the flame to flick out unexpectedly.
This fault is more frequent during extreme winter cold, as a frozen external condensate pipe can cause water to back up into the boiler and extinguish the flame.
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 5P3 — 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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