BoilerFaultCodesThe 6 most common faults
Your boiler has stopped because the water pressure inside the heating system has dropped too low to operate safely.
Locate the external filling loop, usually two silver valves connected by a flexible braided hose underneath the boiler.Open both taps slowly to allow water into the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Fully close both taps to stop the flow and ensure the braided hose is not leaking.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Locate the internal filling loop beneath your boiler.Open the small valve or tap to allow cold mains water into the system.Watch the pressure gauge on the front of the boiler until the needle reaches the green zone (usually 1.0 to 1.5 bar).Close the valve tightly to stop the flow.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Locate the internal filling loop beneath your boiler.Open the filling valve to allow water into the system.Monitor the pressure gauge on the front of the boiler until it reaches 1.5 bar, then securely close the valve.
Your boiler is trying to start up but cannot light the internal flame needed to heat your water.
Full guide for E01Your boiler has detected that it is running too hot and has automatically shut down to prevent damage to its internal parts.
Full guide for E02Your boiler has detected that the flue gases are becoming too hot, so it has safely shut itself down to prevent any damage.
Full guide for E03on the Alpha E-Tec 33
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