BoilerFaultCodesYour boiler is busy clearing out any leftover gases before it tries to ignite again.
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: Boiler is ventilating
What causes this fault?
This code appears when the boiler needs to clear the combustion chamber of old air and gases before it can safely start the ignition process. It is often triggered after a failed start attempt or a sudden interruption in the flame, causing the fan to run at high speed to vent the system. While it usually clears on its own, a persistent C1 code might suggest the fan is struggling to maintain the correct speed or the air pressure sensor is failing to detect the airflow.
DIY fix possible
Wait for up to 5 minutes as this is often a normal part of the boiler's operation sequence.Check if the display changes to a temperature or a different code after the ventilation cycle finishes.Perform a simple reset by pressing the 'R' or 'Reset' button if the code persists for a long period.
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A boiler cover plan would cover faults like C1 — no call-out fees, no surprises.
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