BoilerFaultCodesYour boiler has detected a blockage or a backup of water in the condensation drainage pipe, usually caused by a frozen pipe or a clogged trap.
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 condense trap/pipe/sensor. Call engineer.
What causes this fault?
This fault occurs when the water produced during the combustion process cannot drain away from the boiler, causing it to back up into the internal trap. The most common reasons are a blockage in the external pipework, such as debris or ice, or a failure in the electronic sensor that monitors the water level.
This fault is particularly common during freezing winter temperatures, as the external portion of the condensate drainage pipe is prone to freezing and becoming blocked with ice.
DIY fix possible
Check the white plastic pipe leading outside for signs of freezing or ice blockages.Thaw any frozen external pipes using a hot water bottle or warm (not boiling) water.Restart the boiler once the pipe is clear to see if the drainage resumes.
Find a Gas Safe engineer
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