BoilerFaultCodesThe 6 most common faults
Your boiler's burner has stopped working for safety reasons, meaning the system cannot fire up to provide heat or hot water.
Check that you have enough heating oil in your storage tank.Ensure the oil supply valves are fully open.Press the reset button on the burner control box once; if it fails again, do not keep resetting it and call an engineer.
Your boiler has reached an unsafe temperature and has automatically shut down to prevent damage or dangerous overheating.
Check that all radiator valves are open and not turned off.Ensure there is enough water pressure in the system by checking the pressure gauge.Press the manual reset button located on the control panel or behind the front cover.
Your boiler has shut down because it cannot safely ignite or maintain its flame, often due to a fuel supply issue or a dirty component.
Check that your external oil tank has plenty of fuel.Ensure all oil supply valves between the tank and the boiler are fully open.Press the illuminated reset button on the burner once (if it fails again, do not continue trying and call a technician).
Your boiler has switched itself off because it got too hot, acting as a safety measure to prevent damage.
Wait for the boiler to cool down completely (at least 20-30 minutes).Locate the manual reset button for the high limit thermostat, usually found under a black screw cap on the control panel.Unscrew the cap and firmly press the small reset button inside.Restart the boiler and check that your radiator valves are open and the pump is running.
Your boiler's internal temperature sensor has stopped sending a reliable signal, which means the system cannot safely regulate heat.
Full guide for E1Your boiler has detected a problem with the sensor that monitors exhaust gas temperatures, causing the system to shut down for safety.
Full guide for E2on the Firebird Silver Slimline Systempac 2020
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 Firebird 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
Avoid the next call-out bill
Monthly cover means no unexpected bills when your boiler breaks down.
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