BoilerFaultCodesThe 6 most common faults
Your boiler is not moving water through the system correctly, which is causing it to shut down to prevent overheating.
Check if your radiator valves are openEnsure your system water pressure is between 1.0 and 1.5 barGently bleed air from your radiators using a radiator key
Your boiler has detected that it is heating up very quickly without enough water flowing through it, meaning it is at risk of overheating.
Check if your system water pressure is too low and top it up using the filling loopEnsure all radiator valves are open and not stuck shutTry resetting the boiler using the reset button once pressure is corrected
Your boiler has stopped working because it has detected a fault and shut itself down for safety.
Locate the main on/off switch on the boiler control panel.Switch the boiler to the 'O' (Off) position.Wait for at least ten seconds.Switch the boiler back to the 'I' (On) position to attempt a reset.
Your boiler has become too hot and has switched itself off as a safety precaution to prevent damage.
Check that your radiator valves are open and not turned to the off position.Ensure your system water pressure is correct (if a pressure gauge is visible).Press the 'Reset' button on the front of the boiler control panel once the unit has cooled down.
Your boiler is failing to light its burner and has locked itself out for safety after several unsuccessful attempts.
Check if your gas supply is turned on and other gas appliances are workingCheck if your gas pre-payment meter has creditPress the Reset button once to attempt a restart
Your boiler has detected that its built-in fan is not spinning at the right speed or has stopped entirely, preventing it from safely clearing away exhaust fumes.
Full guide for 160on the Baxi Suprima 40
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