BoilerFaultCodesThe 6 most common faults
Your boiler has failed to ignite or stay lit, causing it to shut down to prevent any safety issues.
Check if your fuel tank has run out of oilEnsure the fuel supply valve is fully openPress the illuminated reset button on the burner controller once
Your boiler's burner has failed to light or stay lit and has shut itself down for safety.
Check if your fuel supply (oil or gas) is turned on and you have fuel in the tankPress the illuminated 'R' or reset button on the burner control unit onceListen for the burner starting up; if it fails again, do not continue to reset
Your boiler's burner has encountered a problem and has shut itself down for safety, meaning you will not have any heating or hot water until it is reset or repaired.
Locate the burner reset button on the control panelPress and hold the reset button for 2-3 secondsWait to see if the burner fires up; if it locks out again, do not continue trying and call a professional
Your boiler's burner has shut down for safety because it failed to light or stay lit correctly.
Check if your fuel tank has run out of oilPress the illuminated reset button on the burner control box onceEnsure any external fuel valves are fully open
Your boiler's oil burner has locked out and stopped working, meaning you will not have any heating or hot water until it is reset or repaired.
Check that you have enough oil in your storage tankEnsure the oil supply valves are fully openPress the illuminated reset button on the burner control box once
Your boiler's burner has encountered a fault and has failed to fire up, meaning you likely have no heating or hot water.
Locate the reset button on the burner control unit (often hidden behind the front cover panel).Press the reset button once firmly.Wait up to two minutes to see if the burner ignites.
on the Viessmann Vitola Biferral
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 Viessmann 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