BoilerFaultCodesThe 5 most common faults
Your boiler has failed to ignite, meaning it cannot light the gas to provide heat or hot water for your home.
Check that your gas pre-payment meter (if you have one) has credit.Ensure your gas stop tap is fully open and other gas appliances are working.Press and hold the 'Reset' button (the one with the flame/cross symbol) for five seconds.
Your boiler has stopped working because the water pressure inside the system is too low for it to operate safely.
Locate the filling loop (a flexible silver hose) underneath the boiler.Slowly open the one or two taps/levers on the filling loop until you hear water entering.Watch the pressure gauge until it reaches between 1.0 and 1.5 bar, then close the taps tightly.
Your boiler has switched itself off because the water inside it has become too hot, usually due to a lack of circulation or a blockage.
Check that your radiator valves are fully open to allow water to flow.Check the boiler pressure gauge and top up to 1.5 bar if it is too low.Reset the boiler using the control knob to see if the fault clears.
Your boiler has shut down to protect itself, likely because it got too hot or failed to light the gas flame.
Turn the main control knob to the 'Off' position.Wait for at least 15 seconds for the system to reset.Turn the control knob back to the 'On' or 'Winter' position and check if the flame ignites.
Your boiler's internal thermometer has stopped working correctly, meaning the system can no longer monitor the temperature of the water used for your heating.
Full guide for F2on the Heatline Capriz 25/28
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 Heatline 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