If a new coil press Up if the same coil press Down. Please be sure to unlock the resistance when changing the atomizer to a new one with a different resistance. Charging your iStick TC 40w. The battery power indicator on the screen will flash when the remaining power level is less than 10%. It can be charged with the USB cable through the USB port on the bottom of the device. It will take about 3.5 hours to get a full charge via a 1A wall adapter. The battery indicator will keep flashing during charging and the screen will go out when fully charged.