BoilerFaultCodesDaikin L Fault Code
The Daikin L fault code means: your boiler is providing hot water at its lowest possible power level, which might result in water that isn't as hot as usual.. It appears on 2 Daikin models in our database.
Technical description: Burner on with minimum DHW capacity
DIY fix possible
Check if any hot water taps are only slightly open and turn them on fullyClean any limescale buildup from showerheads or tap aeratorsRestart the boiler to see if the advisory code clears
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Daikin models that show the L fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Daikin L fault code information on this page is sourced and cross-checked against the official Daikin service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026