A quick video demonstration on how to test your Portable Air Conditioning is cooling.
Using a hygrometer you can test the expelled air temperature of your air conditioning.
Run it for half and hour or so on maximum setting and you should reach a low temperature (16 to 18 degrees but different models may have varying lowest temperature).
If after a couple of hours if your room is still hot, but the hygrometer is showing a low temperature, then your room's heatload is too much for the air conditioning to cool the room down quick enough.
Always make sure the room windows and doors are closed and your exhaust hose is installed as per the instruction manual. Take care to install your window kit or a window seal kit to properly seal the window to avoid losing the cool air from the air conditioning and avoid malfunction.