BoilerFaultCodesYour boiler has stopped working because the pipe that carries water away from the unit is likely frozen or blocked, which you might have noticed as a gurgling sound.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Condensate pipe blockage / Frozen condensate (appliance makes a gurgling noise prior to locking out)
What causes this fault?
This fault happens when the water naturally produced by the boiler cannot drain away because the exit pipe is obstructed. The most common reason is that the water has frozen inside the pipe during a cold spell, creating an ice plug that backs up into the boiler and forces it to shut down for safety.
This fault is almost exclusively seen during winter, as the external pipework is highly susceptible to freezing when temperatures drop below zero.
DIY fix possible
Locate the plastic pipe leading from your boiler to the outside of your property.Check if the end of the pipe is frozen and pour warm (not boiling) water over the external section.Place a hot water bottle or heat wrap around the frozen pipe to gently melt the ice.Reset the boiler by turning the dial to 'Reset' once the pipe is clear.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like L0d — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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