If you have an air conditioner unit that is meant to be installed in a window, it is not intended to be used indoors. It is possible for some window units to be used outdoors under certain conditions, but they will not be as effective.
Spreading of Air
There are two main types of window air conditioners: one that uses water to cool the air and one that brings cooler air from the outdoors indoors.
The ones that bring the air from outdoors to indoors can be used inside, but will act more as a fan than an air conditioner, as it is only spreading around the current air in your home.
The problem with water coolers is that water will inevitably drip and spill out on your floor. If you were able to siphon it out with a hose, it would be possible to keep it indoors, as long as it was near a window so it could get the cooler air inside.
One thing to be concerned about is that many window air conditioners will produce “waste heat” from the compressor and motors. Many times this “heat” is carbon monoxide, which is very damaging to your family’s personal health.