Baxi Section L Fault Code
Also written as SECTIONL — same fault.
The Baxi Section L fault code means: your boiler's waste water pipe is blocked, preventing it from safely draining away the moisture it collects during operation.. It appears on 2 Baxi models in our database.
Technical description: Blockage of the condensate drain or trap
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Baxi models that show the Section L fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Baxi Section L fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026