BoilerFaultCodesYour boiler has detected an issue with how it clears exhaust gases or pulls in fresh air, preventing it from firing up 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: Go to section 'E'
What causes this fault?
This fault occurs when the boiler's safety sensors cannot confirm that the fan is successfully clearing exhaust gases out of the flue. It is often caused by a blockage in the small plastic tubes inside the casing, a buildup of dirt on the fan blades, or a mechanical failure of the air pressure switch itself.
This issue is more frequent during periods of heavy rain or high winds, which can drive moisture into the flue or create pressure fluctuations that interfere with the sensitive air switch.
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 flashing (Air pressure switch proved) — no call-out fees, no surprises.
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Potterton Performa 30 HE 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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