Hi You made a very thick mistake, you never buy the new battery in an emergency lamp and get changed to the house; the change is made where you sell the battery, to make sure everything is fine (or not carry it), otherwise you spent on a very expensive element for an emergency light that does not work. If I misunderstand, the equipment is one of those that have fluorescent, if so, two things can happen: that the tube is depleted, or that the battery is low. Before worrying, leave at minimum charge hours.