Biasi E58 Fault Code
The Biasi E58 fault code means: your boiler has too much water pressure inside the system after being topped up, which has caused it to lock out for safety.. It appears on 2 Biasi models in our database.
Technical description: Filling function of C.H. water completed, but pressure is higher than the maximum pressure for boiler filling.
DIY fix possible
Ensure the blue filling loop taps under the boiler are fully turned off.Locate a radiator bleed valve and use a key to release water into a cloth or container until the pressure gauge drops to 1.5 bar.Reset the boiler to clear the error code.
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Gas Safe Register →Biasi models that show the E58 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Biasi E58 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