Question

Room heaters should be kept down and air coolers higher up in a room. Why ?

Answer 1

Answer:

Cool air is heavier then hot air so it moves downwards. If a cooler is placed at a very low place then it will only cool the floor and not the whole room and the heater is placed at down places because hot air being lighter moves upwards, thus warming both floor and room.

Answer 2

Because air coolers want to be the highest but heaters are afraid of heights