BoilerFaultCodesThe 6 most common faults
Your boiler is failing to light the gas flame, which means you have no heating or hot water until the system is reset or repaired.
Why it happens: This fault occurs when the boiler's control system attempts to light the gas but cannot detect a stable flame. The most common reasons include a lack of gas supply reaching the unit, worn-out electrodes that can no longer produce a spark, or a faulty gas valve that isn't opening correctly.
Check if your gas supply is turned on at the meterTurn the mode selector switch to the 'OFF/RESET' position and then back to 'ON'Check if other gas appliances in your home are working correctly
Your boiler has sensed that it is getting too hot and has shut itself down as a safety precaution.
Why it happens: This fault occurs when the water inside the boiler exceeds a safe temperature limit, triggering a safety sensor to cut the power. The most common reasons are a pump failure preventing heat from being moved away from the boiler, or a blockage in the pipework restricting flow. In some cases, the overheat sensor itself may have become faulty and is reporting a high temperature even if the water is cool.
Check that all radiator valves are fully open to allow water to flow.Wait for the boiler to cool down for at least 30 minutes.Turn the mode selector switch to the 'OFF/RESET' position and then back to 'ON'.
Your boiler has stopped working because the water pressure is too low for it to run safely.
Why it happens: This fault occurs when the system loses the physical water pressure required to push heat around your radiators and protect the internal components from overheating. The most common reason is a slow leak somewhere in your central heating pipework or radiators, though it can also happen if you have recently bled your radiators without topping the water back up.
Locate the filling loop (usually a silver flexible hose) underneath your boiler.Slowly open the small valves on the hose until you hear water flowing.Watch the pressure gauge and close the valves once the needle reaches between 1.0 and 1.5 bar.
Your boiler has failed to ignite properly and has locked itself out for safety.
Why it happens: This fault occurs when the boiler attempts to light the burner but fails to detect a stable flame. The most common reasons are a worn-out ignition electrode that cannot create a spark, a faulty gas valve preventing fuel from entering the burner, or a problem with the internal control board.
Check if your gas supply is turned on at the meterTurn the mode selector switch to the 'OFF/RESET' position and wait for a few secondsTurn the switch back to the 'ON' position to restart the ignition process
Your boiler is having trouble venting exhaust gases or drawing in fresh air, which has caused it to stop working for safety reasons.
Why it happens: This fault occurs when the boiler's safety sensors detect that the fan isn't moving enough air to safely clear exhaust gases from the flue. The most common reasons are a buildup of dirt or debris in the fan or internal tubes, a failing fan motor, or a blockage within the flue pipe itself. To protect you from carbon monoxide, the boiler will not attempt to ignite until this airflow is restored.
Full guide for 03Your boiler has detected an internal fault that is preventing it from operating, and it requires a professional service technician to diagnose and repair it safely.
Why it happens: This fault occurs when the boiler's internal computer receives an incorrect or missing signal from the sensor that monitors hot water leaving the unit. The most common reason is that the sensor has physically failed or developed a short circuit, though it can also be caused by loose or damaged electrical connections between the sensor and the main control board.
Full guide for 06on the Vokera Mynute 28E / 35E
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 Vokera 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