BoilerFaultCodesThe 6 most common faults
Your boiler has switched itself off as a safety precaution because it either failed to light properly or got too hot.
Why it happens: This fault occurs when the boiler's internal sensors detect that the burners failed to light after several attempts or that the internal temperature has become dangerously high. The most common reasons include a lack of gas reaching the burner, a worn-out ignition spark, or a blockage that is preventing water from circulating properly through the heat exchanger.
Locate the mode selector switch on the front control panel.Turn the switch to the 'RESET' position and hold it for a few seconds.Return the switch to the 'ON' position and wait for the boiler to attempt to restart.
Your boiler has detected that the water pressure is too low to operate safely and has switched itself off to prevent damage.
Why it happens: This fault occurs when the water volume inside your central heating system drops below a safe operating level, often due to a small leak in the pipework or a radiator. It can also happen if your radiators were recently bled without the system being topped up, or if an internal component like the expansion vessel is no longer holding pressure correctly. When the pressure drops too low, the boiler shuts down to prevent the internal heat exchanger from overheating and sustaining permanent damage.
Locate the external filling loop (the flexible silver hose) under or near the boiler.Slowly open the one or two taps on the hose until you hear water entering.Watch the pressure gauge and close the taps once the needle reaches between 1 and 1.5 bar.
Your boiler has stopped working because the water pressure inside the system has dropped too low to allow it to run safely.
Why it happens: This fault occurs when the internal water pressure drops below the minimum level required for the boiler to fire up safely. The most common reasons are a slow leak somewhere in your radiator network or the pressure being manually drained away during recent plumbing work.
Locate the filling loop (a flexible silver hose) underneath or near the boiler.Slowly open the one or two taps on the loop until you hear water entering the system.Watch the pressure gauge until it reaches between 1.0 and 1.5 bar, then close the taps fully.
Your boiler has failed to ignite and cannot produce heat, which could be due to a gas supply issue, a blocked exhaust pipe, or an electrical wiring error.
Why it happens: This fault occurs when the boiler's control system attempts to start a flame but fails to detect one after several attempts. It is physically caused by either a lack of fuel reaching the burner, a failure of the spark to ignite the gas, or a sensor that cannot 'see' the flame even if it is lit.
Check if other gas appliances, like a hob, are working to confirm your gas supply is active.Ensure your gas meter has credit and the handle is in the 'on' position.Visually check the outside flue pipe for any obvious obstructions like bird nests or debris.Try resetting the boiler by turning the control knob to the 'Reset' position let it sit for a few seconds.
Your boiler has failed to light, which is often caused by a blocked condensation pipe or an issue with the ignition system.
Why it happens: This fault occurs when the boiler tries to light but fails to detect a flame, causing the system to shut down for safety. The most common cause is a blockage in the condensation pipe or a build-up of debris in the trap, but it can also be triggered by worn ignition parts or an interrupted gas supply.
Check if your gas supply is turned on and other gas appliances are working.If it is freezing outside, check if the plastic condensation pipe leading outdoors is frozen and thaw it with warm water.Press the Reset button on the control panel to see if the boiler restarts.
Your boiler has shut down because it has detected a temperature that is too high, often caused by a blockage or a pump failure.
Why it happens: This fault occurs when the water inside the boiler exceeds a safe temperature, triggering a safety switch to shut the system down. The most common reasons are a pump that has stopped moving water around the system or a blockage in the heat exchanger that prevents heat from escaping.
Check that all radiator valves are fully openEnsure the system water pressure is between 1 and 1.5 barTurn the selector switch to 'OFF/RESET' for a few seconds and then back to 'ON'
on the Vokera Mynute 23E
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