BoilerFaultCodesBiasi E25 Fault Code
The Biasi E25 fault code means: your boiler has detected that the internal temperature is extremely low and has automatically activated its protection mode to prevent the pipes from freezing.. It appears on 7 Biasi models in our database.
Technical description: Boiler in antifreeze
DIY fix possible
Check that your heating timer is set to come on during cold spells to keep the system warm.Ensure the boiler is switched on and not isolated at the electrical spur.If the boiler remains in this mode while the home is warm, turn the boiler off at the mains for 30 seconds and restart it.
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Biasi models that show the E25 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Biasi E25 fault code information on this page is sourced and cross-checked against the official Biasi service / installation manuals for each affected model.
- Biasi Activ A manual (PDF)
- Biasi Advance Plus 16S 25S 30S manual (PDF)
- Biasi Basica Combi manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026