BoilerFaultCodesThe 6 most common faults
Your boiler has detected that there is not enough water pressure in the system to operate safely, causing it to shut down.
Locate the filling loop (usually a silver braided hose with small valves) underneath the boiler.Slowly open both valves to allow water into the system while watching the pressure gauge.Close both valves tightly once the pressure gauge reaches between 1.0 and 1.5 bar.
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 detected an issue with how it clears waste gases or a blockage in the drainage pipe, causing it to shut down for safety.
Check the white plastic condensate pipe outside for signs of freezing or blockage.If frozen, wrap the pipe in a warm (not boiling) cloth or pour warm water over it to melt the ice.Restart the boiler using the reset button once the pipe is clear.
Your boiler has failed to light or maintain a flame, meaning you have no heating or hot water because the burner has shut down for safety.
Check if other gas appliances, like a hob, are working to confirm your gas supply is active.If you have a prepaid gas meter, check that you have remaining credit.Press and hold the 'Reset' button for 2-5 seconds to see if the boiler restarts.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Locate the filling loop (usually a silver flexible hose) underneath the boiler.Slowly open the one or two taps/levers on the hose until you hear water flowing.Watch the pressure gauge and close the taps once the needle reaches between 1 and 1.5 bar.
Your boiler has become too hot and has automatically shut down to prevent damage or safety issues.
Check that all radiator valves are fully open to allow water to circulateEnsure there is enough pressure in the system by checking the gaugeOnce the boiler has cooled down, press the reset button
on 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