(1)How about the warranty of the air coolers?

1-2 year warranty for the whole machine.

(2)What are the differences between air coolers and air conditions?

The 3-step air cooling process is very simple and no less effective than morden refrigerated air conditioning technologies.

Step-1: 

An air moving system pulls fresh outside air and drives it through the moist cooling pad. 

Step-2:

The water in the pads evaporates, bringing down the temperature of the air passing through the cooing pads.

Step-3:

Then blows the cool 100% fresh air into the room.