Your boiler is perfectly healthy, but it is currently waiting for a signal from your wall-mounted thermostat to tell it to turn the heating on.

DIY fix possible

Check your wall thermostat or heating controller and turn the target temperature up higher than the current room temperature.Check if your thermostat is set to 'Auto' or 'Schedule' mode and ensure a heating period is currently active.Replace the batteries in your wireless thermostat if the display is blank or dim.