BoilerFaultCodesThe 6 most common faults
Your boiler has stopped working because the amount of water inside your heating system has dropped below the required level.
Locate the filling loop, which is usually a flexible silver hose under the boiler connecting two pipes.Open the valves on both ends of the loop to allow water into the system, keeping an eye on the pressure gauge.Once the needle reaches the green zone (typically 1.0 to 1.5 bar), tightly close both valves and disconnect the hose if required.
Your boiler has detected that a safety device or connection is missing or has been triggered, causing it to stop operating as a precaution.
Locate the electrical terminal block inside your boilerIdentify terminals 14 and 15Ensure a bridge wire or link is securely fitted between these two terminals
Your boiler is struggling to pump water around your heating system, causing the water inside to heat up too quickly and triggering a safety shutdown.
Check that all your radiator valves are fully open.Ensure your system pressure is set correctly between 1.0 and 1.5 bar.Check if your hot water or heating flow is restricted by a closed isolation valve near the boiler.
Your boiler has stopped because the water pressure inside your heating system has dropped too low to operate safely.
Locate the external filling loop, which is usually a braided silver hose connecting two pipes under the boilerOpen the small valves at both ends of the hose to allow mains water into the systemWatch the pressure gauge on the front of the boiler until the needle reaches the green zone (typically 1.0 to 1.5 bar)Close both valves tightly and remove the filling loop if required by your specific model
Your boiler has lost its internal configuration settings and needs to carry out a specific self-adjustment process to ensure it burns gas safely and efficiently.
Full guide for E72Your boiler is trying to start but cannot light the internal flame, so it has shut down as a safety precaution.
Full guide for 01on the Alpha Intec2 25 28XE
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 Alpha 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