Your boiler is currently running in a manual testing mode used by engineers to check emissions, which overrides your normal temperature settings.

DIY fix possible

Locate the button with a 'chimney sweep' or 'flame' icon on the control panel.Press and hold the button for at least five seconds until the display returns to the normal temperature reading.Switch the boiler power off and back on at the fused spur switch to reset the software if the code persists.