BoilerFaultCodesYour boiler has detected an issue moving air or exhaust gases safely through the system, causing it to shut down 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: Air pressure switch fault - The flue or fan is blocked or faulty.
What causes this fault?
This fault occurs when the boiler's safety sensors detect that harmful exhaust gases aren't being pushed out of the flue correctly. The most common reasons are a buildup of dirt on the fan blades, a blockage in the plastic tubes leading to the sensor, or a mechanical failure within the fan itself. Because these components ensure the boiler is breathing safely, the system will prevent the burner from lighting if any restriction is detected.
This fault often appears during the first cold spell of autumn when a boiler that has been idle over summer is suddenly forced to work at high speeds, causing aged fans to seize or struggle.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like neon illuminated (fan/flue symbol) — no call-out fees, no surprises.
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Potterton Performa 24 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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