BoilerFaultCodesThe 6 most common faults
Your boiler has shut down because it has detected it is getting too hot, usually due to a lack of water flow or a circulation problem.
Check that your system pressure is between 1.0 and 1.5 bar on the gaugeEnsure all radiator valves and isolation valves under the boiler are fully openTry resetting the boiler by turning the selector switch to 'R' for five seconds
Your boiler has stopped working because the water pressure is too low for it to run safely.
Check the pressure gauge on the front of the boiler or under the casingLocate the filling loop (a flexible silver hose with small lever valves)Slowly open the valves to top up the water until the gauge reads between 1.0 and 1.5 barClose the valves tightly and restart the boiler
Your boiler has failed to light because it either isn't receiving gas or is unable to detect a flame.
Check if other gas appliances, like a hob, are working to confirm your gas supply is onCheck if your gas meter has credit (if using a pre-payment meter)Check if the condensate pipe (the white plastic pipe outside) is frozen and defrost it with warm waterPress and hold the reset button for five seconds
Your boiler has detected that water is not circulating properly before the burner starts up, often caused by an air lock or a blockage in the system.
Check that your system pressure is between 1.0 and 1.5 barEnsure all radiator valves and isolation valves are fully openGently bleed your radiators to remove any trapped air
Your boiler has become too hot and has shut down as a safety precaution to prevent damage.
Turn off the boiler and allow it to cool completelyCheck all radiator valves are openBleed your radiators to remove trapped airCheck the system pressure and top up if it is below 1.0 barPress the reset button on the boiler
Your boiler has too much water inside it, which puts extra stress on the system and has caused it to stop working for safety.
Check that the filling loop valves are fully closed and not leaking water into the systemBleed water from a radiator using a bleed key to reduce the system pressureMonitor the pressure gauge until it returns to around 1.0 to 1.5 barReset the boiler once the pressure is within the normal operating range
on the Baxi Netaheat
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