BoilerFaultCodesYour boiler is struggling to light because the small pipe that starts the main flame is clogged with dust or debris.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Blocked pilot filter
What causes this fault?
This fault occurs when the tiny hole that allows gas to reach the pilot light becomes restricted by a buildup of household dust or soot. Because the pilot flame cannot stay strong enough to heat the safety sensor, the boiler fails to ignite the main burner as a security precaution.
This issue is frequently seen in autumn when boilers are turned on for the first time after being inactive all summer, as settled dust is more likely to cause a blockage.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like A(3) — no call-out fees, no surprises.
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Potterton Flamingo RS40 RS50 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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