BoilerFaultCodesBaxi 70 Fault Code
The Baxi 70 fault code means: the number 70 on your boiler is not a fault code, but a label indicating that your boiler is a 70,000 btu/h model.. It appears on 2 Baxi models in our database.
Technical description: 20.5kW (70,000 Btu/h)
DIY fix possible
Check your boiler's manual or data plate to confirm that 70 refers to the unit's heating capacity rather than a flashing error light.If the boiler is actually showing other flashing lights, consult your user manual for the specific fault sequence.If the boiler is working normally, no action is required.
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Baxi models that show the 70 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Baxi 70 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 7 July 2026