BoilerFaultCodesThe 6 most common faults
Your boiler is struggling because it cannot detect enough water circulating through the system or the pressure level has dropped too low.
Check the pressure gauge on the front of the boiler; if it is below 1 bar, locate the filling loopOpen the filling loop valves to allow water into the system until the needle reaches 1.5 barClose the filling loop valves tightly and restart the boiler
Your boiler has stopped working because water is not circulating correctly through the system to prevent it from overheating.
Check that your system pressure is between 1.0 and 1.5 bar on the pressure gaugeEnsure all radiator valves and isolation valves under the boiler are fully openGently bleed your radiators to remove any trapped air that might be blocking flow
Your boiler has reached an unsafe temperature or detected excessive heat in the exhaust, causing it to shut down for safety.
Check that all radiator valves are fully openEnsure the boiler pressure is between 1.0 and 1.5 barAllow the unit to cool down and attempt a reset by turning the selector knob to 'R' for five seconds
Your boiler is failing to light properly or stay lit, meaning your heating and hot water will not work until it is reset or repaired.
Check if your gas supply is turned on at the meterCheck if other gas appliances like a hob are workingTurn the selector switch to 'R' (Reset) for 5 seconds and then release
Your boiler has failed to ignite the gas burner, which means it cannot heat your water or radiators.
Locate the reset button (usually marked with an 'R' or a flame symbol) and hold for 5 seconds.Check that your gas emergency control valve is in the 'on' position and other gas appliances are working.Ensure your prepaid gas meter has sufficient credit.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage.
Full guide for 23on the Baxi Combi Elite
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