BoilerFaultCodesYour boiler has stopped working because the pipe that carries away excess wastewater is blocked, often due to a buildup of debris or freezing weather.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Condensate trap blocked
What causes this fault?
This fault occurs when the internal trap or the external drainage pipe becomes obstructed, preventing the boiler from safely disposing of the wastewater it produces during operation. The most common reason is a buildup of sludge and debris within the trap itself, or an ice blockage in the external pipework following a cold spell.
This fault is significantly more common during winter, as the wastewater in the external discharge pipe can freeze and back up into the boiler.
DIY fix possible
Check the white plastic pipe leading outside to see if it is frozen or blocked.If frozen, gently pour warm (not boiling) water over the external pipe to melt the ice.Carefully check the plastic trap underneath the boiler for visible blockages if accessible without opening the boiler casing.Restart the boiler once the blockage is cleared.
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