BoilerFaultCodesThe 6 most common faults
Your boiler has detected that water is not moving through the system properly, which is causing it to shut down to prevent overheating.
Check that your system pressure is between 1 and 1.5 bar on the pressure gaugeEnsure all radiator valves are fully openBleed your radiators to remove any trapped air pockets
Your boiler has likely stopped heating because the water inside has become too hot or the temperature sensors are reporting an incorrect reading.
Turn off the boiler at the electrical switchWait 10 minutes for the unit to cool downTurn the selector switch to the 'Reset' position for five seconds and then back to the desired mode
Your boiler has got too hot and has shut itself down as a safety precaution.
Check that all radiator valves are open and not turned off.Ensure your system water pressure is between 1 and 1.5 bar on the gauge.Turn the selector switch to the reset position for five seconds, then back to the desired mode.
Your boiler has tried to light the gas five times without success and has now locked itself out for safety.
Check that your credit or prepaid gas meter has sufficient funds.Ensure other gas appliances in your home, like a hob, are working correctly.Press and hold the reset button for five seconds to see if the boiler restarts.
Your boiler's fan is not spinning correctly, which means the system cannot safely clear waste gases and has shut down as a precaution.
Full guide for 4 red flashesYour boiler's internal memory chip or main control board has developed a communication fault and cannot remember its settings.
Full guide for 5 red flasheson the Baxi Performa
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 Baxi 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