BoilerFaultCodesYour boiler has stopped working because it thinks the waste water pipe is full or there is an issue with the sensor that detects blockages.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Condensate sensor fault
What causes this fault?
This fault occurs when the boiler's internal safety sensor detects that the waste water, known as condensate, is not draining away properly. It is usually caused by a physical blockage in the external pipework or a build-up of debris within the boiler's collector trap. In some cases, the sensor itself may have failed or become corroded, wrongly telling the boiler that it is full of water.
This fault is significantly more common during freezing winter temperatures, as the external condensate pipe can freeze, causing water to back up into the boiler.
DIY fix possible
Check the external plastic condensate pipe for signs of freezing if the weather is very cold.Thaw a frozen external pipe using a hot water bottle or warm (not boiling) water.Check that the condensate discharge pipe is not blocked by debris or leaves.
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