BoilerFaultCodesYour boiler is performing a routine safety check by blowing air through the system to clear any leftover gases before or after it fires up.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: 15 seconds ventilation phase before or after operation of the unit
What causes this fault?
This code appears when the boiler's fan runs to clear the combustion chamber of any residual gases, ensuring the unit is safe to ignite. It is physically triggered by the fan spinning up to create a specific airflow, which is then confirmed by the internal pressure sensors. While usually a normal operational step, if it persists, it could indicate that the fan is struggling to reach the required speed or the air pressure switch is failing to sense the flow.
DIY fix possible
Observe the display to see if the code disappears after 15-30 secondsEnsure there are no obstructions around the external flue pipeReset the boiler if the code remains on the screen for an extended period
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