BoilerFaultCodesYour boiler has detected an issue with how air and exhaust gases are moving through the system, 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’: Check electrical and pressure tube connections, blockage of pressure tubes, restriction in flue, or venturi.
What causes this fault?
This fault occurs when the boiler's internal safety sensor cannot confirm that the fan is successfully pushing exhaust gases out of the flue. It is often caused by a small blockage in the narrow sensing tubes, a worn-out fan motor, or a buildup of debris in the air intake that prevents the correct pressure from being reached. Because the boiler cannot guarantee that harmful gases are being safely removed, it prevents the burner from lighting.
This issue is frequently seen during periods of high winds or extreme cold, as strong gusts can interfere with flue pressure and spiders or debris often seek shelter in the external terminal during autumn.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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