BoilerFaultCodesThe 6 most common faults
Your boiler has failed to light the gas flame, meaning it has shut itself down for safety and cannot provide heating or hot water.
Check if your gas supply is active by testing another gas appliance like a hob.Perform a reset by turning the control knob to 'R' for five seconds and then back to the on position.Verify that your condensate pipe (the plastic pipe leading outside) isn't frozen if it is currently winter.
Your boiler has switched itself off because it has detected that it is getting too hot inside.
Check that all radiator valves are open to ensure water can flow.Ensure there are no blockages in the system by checking for trapped air in radiators.Press the Reset button on the boiler control panel once to see if it restarts.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Locate the filling loop (usually two silver valves connected by a flexible hose underneath the boiler)Open the valves slowly to allow water into the system until the pressure gauge reads between 1.0 and 1.5 barClose both valves tightly and restart the boiler
Your boiler is failing to recognise that the flame has lit correctly, causing the system to shut down for safety.
Check if other gas appliances in your home, like a gas hob, are working to ensure gas is reaching the propertyCheck that your prepaid gas meter has credit, if applicablePress the Reset button on the boiler control panel and hold for five seconds
Your boiler has switched itself off because it has detected that it is getting too hot or there is a problem with the exhaust temperature.
Check that all radiator valves are fully openEnsure the system pressure is between 1 and 1.5 bar on the gaugePress the 'Reset' button on the front control panel and hold for 2-5 seconds
Your boiler has stopped working because the internal water pressure has dropped too low for it to operate safely.
Locate the external filling loop, which is usually a flexible silver braided hose with one or two valves located underneath the boiler.Gradually open the valve(s) to allow mains water into the system while watching the pressure gauge on the front panel.Stop filling once the needle reaches the green zone, typically between 1.0 and 1.5 bar, then ensure the valves are fully closed.
on the Biasi Activ A
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