BoilerFaultCodesThe 6 most common faults
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Locate the external filling loop, which is a flexible braided hose underneath your boiler connected to two valves.Open the valves slowly to allow cold mains water to enter the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close both valves tightly to prevent over-pressurisation.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Locate the external filling loop, usually two silver valves connected by a braided metal hose underneath the boiler.Open the valves 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.Close both valves firmly and ensure they are fully tightened.
Your boiler's control panel has detected that one of its buttons is permanently held down or jammed, preventing the system from operating normally.
Switch off the boiler power at the fused spur or mains switch.Carefully inspect the control panel buttons or digital interface for any dirt, debris, or sticky residue that might be holding a button in place.Gently press or wiggle the buttons to see if they can be un-stuck, then power the boiler back on to see if the code clears.
Your boiler is struggling to push water around your heating system because there is trapped air bubbles inside the pump or a blockage in the pipes.
Check your boiler pressure gauge to ensure it is between 1.0 and 1.5 barBleed all radiators in your home starting from the downstairs and moving upstairsTop up the system pressure to 1.5 bar using the filling loop if it dropped after bleeding
Your boiler has failed to light because it cannot detect a flame, which means your heating and hot water have stopped working.
Full guide for E01Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent any damage or safety issues.
Full guide for E02on the Alpha E-Tec Plus
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