How do I fill the water tank in my L48Acw20 Air Cooler?

First, unplug the unit from the mains socket. Turn the water tank switch anticlockwise at the rear of the unit and slide the tank out. Pour water up to the MAX level and add ice box(es) into the tank. Slide the tank back in and turn the switch downwards to lock it securely. You may add extra ice boxes to improve cooling performance.