Zone, all-air systems
It will be shown that the constraint on the Central train station all air supply systems for large ducts and the need to organize the dual duct or re-heating of each branch. If the conditioned space can be divided into several zones or areas where the load is fairly constant, one zone of the air-handling unit with localized ducts may be able to meet the conditions without re-heat in its branches. The success of such a system will depend on the choice of areas. Large open offices can be considered as one zone, if windows or neighboring opposite wall cause daily changes in the solar load. In such cases, it will be better to split the floor in arbitrary locations, depending on the aspect windows. Some local changes will occur and there may be in the " hot spots " close to the Windows, but the condition in General, should be acceptable standards of comfort.
Conditioning devices for the zones can be of several types:
- Direct expansion supplied with refrigerant from the Central plantroom
- Chilled water for air
handling unit with chilled water from a package or from the Central plantroom
- Water-cooled packaged direct expansion unit, using a condenser water from an external tower
- Remote condenser (split) with air cooling with direct expansion unit; remote condenser, perhaps, on the roof
- With air cooling with direct expansion unit installed, adjacent to the outer wall, or through the roof
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Air-Conditioning