A:Answer Hi Tyler, this is Kelly with Dyson. You do not need to fully charge the machine again to use it, however for best results and to achieve optimum run time, you would want to fully charge it. Keep in mind too, if using the machine in MAX suction mode, you will get less run time. We would also suggest letting the machine cool down a bit, prior to charging the battery.
Best wishes,
Kelly
Dyson Customer Support
