BoilerFaultCodesThe 6 most common faults
01
A 01 High Engineer
Your boiler has failed to light its burner, which means it cannot produce any heating or hot water for your home.
Full guide for A 0102
A 02 High Engineer
Your boiler has detected that it is overheating and has automatically shut itself down to prevent any damage or safety issues.
Full guide for A 0203
A 03 High Engineer
Your boiler is struggling to clear exhaust gases because the internal fan that pushes air out through the flue has stopped spinning correctly.
Full guide for A 0304
A 07 High Engineer
Your boiler has detected that the water inside the system is getting far too hot, which has caused it to shut down to prevent damage.
Full guide for A 0705
A 08 High Engineer
Your boiler has sensed that the water returning to it from your radiators is too hot, causing it to shut down to prevent damage to the system.
Full guide for A 0806
A 09 High Engineer
Your boiler has detected an issue with the sensor that monitors exhaust gases or internal heat, forcing it to shut down for safety.
Full guide for A 09on the Vokera Verve
Ignition electrodeGas valvePCBHigh limit thermostatNTC thermistorPump
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 Vokera 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