BoilerFaultCodesYour boiler has detected a problem safely clearing waste gases through the flue pipe, which has caused the system 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: Problem with fan/flue. Re-set as described for code 01.
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the fan isn't moving enough air to safely expel exhaust gases through the flue. The most common reasons are a failing fan motor, a blockage in the flue pipe, or a build-up of debris in the small plastic tubes that monitor air pressure. Because the boiler cannot guarantee that harmful fumes are being moved outside, it shuts down as a critical safety precaution.
This fault can be more frequent during periods of heavy wind or extreme cold, as high gusts can disrupt the air pressure balance and ice can block the flue terminal.
DIY fix possible
Locate the mode selector switch on the front control panel.Move the switch to the 'OFF/RESET' position and wait for approximately 10 seconds.Move the switch back to either the 'Hot Water Only' or 'Heating and Hot Water' position to attempt a restart.
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