BoilerFaultCodesThe 6 most common faults
Your boiler has stopped working because it failed to light the flame after several attempts, usually due to a lack of gas supply or an ignition problem.
Why it happens: This fault occurs when the boiler attempts to start up but cannot successfully establish or detect a steady flame. The most common reasons are a temporary interruption in the gas supply, a build-up of carbon on the ignition parts, or a component failure that prevents the spark from firing.
Check if other gas appliances in your home, like a hob, are working to confirm gas supply.Verify that your gas meter has credit if you use a pre-payment meter.Press the Reset button on the boiler control panel to see if the system restarts.
Your boiler has shut down because it has reached an unsafe temperature, triggered by a safety sensor that prevents the unit from overheating.
Why it happens: This fault occurs when the water inside the boiler gets too hot, causing a safety switch to Cut off the system to prevent damage. The most common reasons are a pump failure that stops water from moving or a blockage in the heat exchanger that restricts flow.
Check that all radiator valves are fully open to allow water to circulate.Ensure your system pressure is topped up to between 1 and 1.5 bar.Turn the boiler off and on again, or press the 'Reset' button to clear the lockout once the system has cooled down.
Your boiler has detected that the water pressure is either too low or the sensor that monitors it is not communicating correctly.
Why it happens: This fault occurs when the boiler's internal sensor detects that there isn't enough water pressure to safely heat your home, or if the sensor itself has developed an electrical fault. The most common reason is a gradual loss of water through a small leak or from bleeding your radiators, which drops the pressure below the required operational limit. When this happens, the boiler shuts down as a safety precaution to prevent the internal components from overheating.
Locate the pressure gauge on the front of the boiler or via the digital screen.If the pressure is below 1 bar, use the filling loop underneath the boiler to carefully top it up to 1.5 bar.Restart the boiler to see if the error clears once the pressure is stable.
Your boiler has detected that the water pressure is incorrect or the sensor that monitors it is not communicating properly.
Why it happens: This fault occurs when the boiler's internal sensor detects that there is not enough water pressure to operate safely. The most common reason is a slow leak somewhere in your central heating system or air being released from the radiators, which causes the pressure to drop below the required threshold. It can also be caused by the sensor itself becoming blocked with debris or failing electronically.
Check the pressure gauge on the front of the boiler; it should be between 1 and 1.5 bar.If the pressure is too low, use the filling loop valves to top up the system until the gauge reaches 1.2 bar.Reset the boiler to see if the fault clears.
Your boiler has detected a flame when there shouldn't be one, or the sensor incorrectly thinks a fire is lit, causing it to shut down for safety.
Why it happens: This fault occurs when the boiler's control system detects a flame signal at a time when the gas should be turned off. This is often caused by a faulty sensor sending a false signal, a gas valve that is leaking slightly, or a glitch in the main circuit board that misinterprets electrical background noise as a fire.
Full guide for E011Your boiler has stopped working because the fan that removes waste gases is not spinning or communicating correctly with the system.
Why it happens: This fault occurs when the boiler's control system detects that the fan is not spinning at the required speed to safely clear combustion gases from the unit. The most common reasons are a mechanical failure within the fan motor itself, a loose connection in the internal wiring, or a fault on the main circuit board failing to send power to the fan.
Full guide for E030on the Vokera Evolve
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