BoilerFaultCodesThe 6 most common faults
01
Lack of power supply High DIY-safe
Your boiler is not receiving any electrical power, which stops it from working entirely.
What to try first
Check that the fused spur switch supplying the boiler is turned on.Check your home's fuse box or consumer unit to see if a trip switch or fuse has blown.Try plugging a lamp into a nearby socket to verify the electrical supply is working.
02
Faulty primary circuit High DIY-safe
Your boiler has temporarily stopped working because the water pressure inside the heating system has dropped too low.
What to try first
Locate the filling loop underneath your boiler.Open the valves slowly to let water into the system until the pressure gauge reads between 1.0 and 1.5 bar.Close the valves tightly and reset your boiler.
03
Lack of burner ignition High Engineer
Your boiler is trying to start up, but it is failing to light the flame to provide heating and hot water.
Full guide for Lack of burner ignition04
Safety thermostat lock out High Engineer
Your boiler has shut down completely for safety because it detected that the water inside has gotten too hot.
Full guide for Safety thermostat lock out05
Flame detection error High Engineer
Your boiler is trying to start up, but it cannot sense the flame once the gas ignites, so it safely shuts itself down to prevent any gas build-up.
Full guide for Flame detection error06
Faulty air pressure sensor High Engineer
Your boiler has detected an issue with the sensor that manages internal airflow, so it has safely shut down to prevent incorrect operation.
Full guide for Faulty air pressure sensoron the Biasi Riva Plus HE 28C ErP
FusePrinted Circuit Board (PCB)Filling loopPressure relief valvePressure sensorIgnition electrode
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
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