can you use a window ac without a window

Yes, but only if the hot air and condensation can be vented outside somehow. A window AC is built to push heat out the back, so using it with no real exhaust path usually means poor cooling, extra moisture, and a lot of wasted power.

What works

• A door, wall opening, or other ducted vent to the outside can work if it safely carries the exhaust outdoors.

• A temporary setup through a sliding door is possible in some rooms, but it needs sealing so hot air does not leak back in.

• If you do not have a practical way to vent it, a portable AC is usually the better choice because it is designed for that kind of setup.

What to avoid

• Do not run a window AC fully indoors with no exhaust route.
• Do not let it dump hot air into another room unless you are okay heating that space too.

• Do not ignore condensate drainage, because water can build up indoors and cause damage.

Best practical answer

If you mean “Can I just plug it in and use it anywhere in the room?” the answer is no, not effectively. If you mean “Can I adapt it with proper venting?” then yes, but it is a workaround, not the ideal setup.

TL;DR: A window AC needs an outside exhaust path to work properly. Without a window, use a vented workaround or buy a portable AC instead.