Abstract: When in operation, devices for telecommunications installed in rooms generate a considerable amount of heat. This takes place continuously, and a maximum temperature must not be exceeded. In order to obtain reserve time for an air cooling system having a reserve time system with a guaranteed low temperature level of the liquid for the reserve time system, an evaporator (2) for the air cooling system is provided with a liquid circuit (2b) which is connected with a liquid tank (7). Liquid is circulated continuously through the evaporator with the liquid circuit, where it is cooled by the cooling medium for the air cooling system, at the same time as the inside air is cooled by the same evaporator. The continuous cooling and circulation of the liquid in the tank ensures that there is always the coldest possible liquid available when the ordinary cooling system is not working.

Abstract: A system for cooling heat generating components in a closed space, for example, telecommunications equipment in rack cabinets in an enclosure includes a cooling unit operating with combined displacing air distribution and gravity air flow. Cooled air is distributed at low speed at a bottom of the closed space to contact the components from below. The cooled air displaces warmer air around and in the components for cooling. The warmer air moves upward in the space and is taken into the cooling unit at an upper intake opening. Air flow in the space is at a speed sufficiently low to avoid turbulence and mixing of the cooled and warmed air flows.