It should work, however backup time will be rather limited, some "hacks" actually augment the internal battery with an external one (say a car battery). Based on the power requirements of your projector you may* need to get a larger unit, 120V times 14A is 1680VA, however typically the power listed is the maximum power draw, not necessarily the continuous usage. In a pinch I would get this unit, ideally a higher capacity unit would likely be more appropriate.