How does a stand-alone inside air-conditioner work

See also this thread:

Which references this one as well:

But yeah, “no installation/venting/outside access required” are almost always underpowered swamp coolers (sometimes with ice added), standing fans with woo, or out and out frauds.

Yes, I know the OP is referencing a tower, not the mini-mini variants, but same technology (or lack of) almost all the time. At least with a tower, you’ve got a bigger fan!

ETA - of course, if it’s the same/similar to this:

Then it’s calling itself a portable air conditioner when it’s described operation is ONLY of a fan. So, more scammy than usual.