BoilerFaultCodesThe 6 most common faults
Your boiler is struggling to detect the water flowing through it, which is likely caused by low system pressure.
Check your boiler pressure gauge; if it is below 1 bar, find the filling loop (usually a silver braided hose under the boiler).Open the valves on the filling loop to allow water into the system until the gauge reads 1.5 bar.Close the valves tightly and restart the boiler.
Your boiler has detected that the water pressure in your heating system has dropped too low and needs to be topped up to function correctly.
Locate the external filling loop, which is usually a flexible silver hose connecting two pipes underneath the boiler.Slowly open the tap or valve on the filling loop to allow water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the tap or valve tightly once the correct pressure is reached to stop the flow.
Your boiler has detected that there is not enough water circulating inside the system to operate safely.
Check your boiler's pressure gauge on the front panel to see if it has dropped below 1 barLocate the external filling loop—usually two small valves connected by a flexible silver hose under the boiler.Open the valves slowly to allow water into the system until the gauge reads between 1 and 1.5 bar, then close the valves tightly
Your boiler has failed to light the flame needed to heat your home and has safely shut itself down as a precaution.
Full guide for Er 01Your boiler has detected that it is overheating and has shut itself down to prevent any damage or safety hazards.
Full guide for Er 02Your boiler has stopped working correctly because the system has encountered a general safety error and has shut itself down to prevent damage.
Full guide for Er 03on the Biasi Advance Plus
Based on parts cited in our fault code database. Your engineer will confirm what's actually needed after diagnosis.
Call a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Biasi shows an Emergency or High severity code
- The boiler keeps locking out after repeated resets
- You've tried the DIY checks and the fault hasn't cleared
- There's visible water leaking from the boiler
- The flame is yellow or orange instead of blue