> But I think it’s fair to say that in most US elevator installations, when the elevator is operating in its normal mode (not service or fire mode), the button

> But I think it’s fair to say that in most US elevator installations, when the elevator is operating in its normal mode (not service or fire mode), the button has no effect. Not quite. There is both a minimum door hold time and a door hold time. If the door hold time is longer than the minimum door hold time, the close door button works after the minimum door hold time. Only if these times are the same does the button effectively do nothing.