Biasi hP Fault Code
Also written as HP — same fault.
The Biasi hP fault code means: your boiler is currently running a manual test mode to check its performance at the lowest power setting and is not experiencing a functional fault.. It appears on 2 Biasi models in our database.
Technical description: minimum output in heating mode (Chimney sweep function)
DIY fix possible
Wait for the chimney sweep test to finish automatically (usually takes 15 minutes)Press the 'Reset' or 'Mode' button to manually exit the test modeTurn the power off and back on again if the code persists
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Gas Safe Register →Biasi models that show the hP fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Biasi hP fault code information on this page is sourced and cross-checked against the official Biasi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026