BoilerFaultCodesTechnical description
Condensate sensor fault / water in the trap
What causes this fault?
This fault occurs when the boiler detects that the liquid waste produced during the heating process cannot drain away correctly, causing the internal trap to fill up. The most common reason is a blockage in the narrow drainage pipes or a build-up of debris within the condensate trap itself, which triggers a sensor to shut the system down to prevent water damage.
This fault is frequently seen during periods of extreme cold, as the external portion of the waste pipe can freeze solid, preventing any liquid from escaping the boiler.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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