Boxcoolers are systems especially designed for the commercial shipping industry. They cool the primary circuit with raw water. These systems make settling tanks, valves and extra raw-water pumps redundant. Boxcoolers may be placed both athwartship and alongship. They are obviously very compact and suitable for riverwater and brackish water. With a coating they are also suitable for seawater. Standard delivery includes a welding edge, making drilling or tapping of holes unnecessary. The interior is demountable if the top equals the empty waterline.