BoilerFaultCodesThe 6 most common faults
Your boiler has failed to light or stay lit and has locked itself out for safety.
Check that your gas emergency control valve is in the 'on' positionCheck if other gas appliances in your home are working to confirm gas supplyPress the 'Reset' button on the boiler control panel once
Your boiler has detected that the water pressure is incorrect or the sensor that monitors it has stopped working properly.
Check the pressure gauge on the front of the boiler; it should be between 1.0 and 1.5 bar.If the pressure is too low, use the filling loop to top up the system until the gauge reaches 1.2 bar.Restart the boiler once the correct pressure is reached to see if the code clears.
Your boiler has detected that the water pressure is too low for it to operate safely and has temporarily stopped working.
Locate the filling loop (usually two silver braided hoses or blue handles) underneath the boiler.Open the valves slowly to allow water into the system while watching the pressure gauge.Close both valves once the pressure gauge reaches 1.5 bar.
Your boiler has been reset too many times in a short period and has now locked itself completely for safety.
Turn the boiler electrical power off at the fused spur switchWait for at least 30 secondsTurn the power back on to clear the lockout memory
Your boiler has detected a flame when there shouldn't be one, which means the system has shut down for safety reasons.
Full guide for E011Your boiler has switched itself off because it has detected that the water inside has become too hot, acting as a safety precaution to prevent damage.
Full guide for E020on the Vokera Unica MAX System
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
Avoid the next call-out bill
Monthly cover means no unexpected bills when your boiler breaks down.
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