BoilerFaultCodesThe 6 most common faults
Your boiler has detected that it got too hot or lost power, so it has automatically turned itself off to stay safe and needs to be reset.
Turn the boiler settings dial to the 'Reset' position (or press the reset button if applicable).Wait for the boiler to cycle through its ignition sequence.If the light stays on, check if your heating system has enough water pressure or if a radiator valve is stuck closed.
Your boiler has likely stopped working because it reached a temperature that is too high, causing it to shut down for safety.
Turn the control knob to the OFF positionWait for at least 10 secondsTurn the control knob back to the ON position and check if the boiler fires up
Your boiler has failed to light after several attempts and has locked itself for safety.
Check that your gas pre-payment meter (if you have one) has credit.Ensure there are no outages in your local gas supply.Restart the boiler by turning the selector switch to 'Reset' or 'Off' for five seconds, then back to 'On'.
Your boiler has switched itself off because it has gotten too hot, which is a safety mechanism to prevent damage.
Check that all radiator valves are fully openEnsure your system pressure is at the correct level (usually 1.0 to 1.5 bar)Locate the reset button on the bottom of the boiler and press it once to restart
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent damage.
Full guide for Red neon illuminatedYour boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Full guide for Overheat (Red LED)on the Baxi Solo 3 40 PF
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