BoilerFaultCodesYour boiler is likely unable to drain away the condensation it produces naturally, causing it to 'choke' and shut down.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: If the appliance is restarted it will make a gurgling noise prior to locking out
What causes this fault?
This fault occurs when the wastewater produced during the heating process cannot flow out of the boiler, causing the internal trap to overflow. The most common reason is a blockage in the external pipework, which prevents the unit from draining and effectively drowns the burner. This backup of water triggers a safety sensor to shut the system down to prevent internal damage.
This fault is extremely common during freezing winter temperatures, as the external condensate pipe can freeze solid and create a backup of water.
DIY fix possible
Locate the plastic pipe leading from the boiler to your outside drain.If it is freezing cold outside, gently pour warm (not boiling) water over the outdoor section of this pipe to melt any ice blockages.Restart the boiler by pressing the reset button.
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