Packaged air cooling units
In this there is no clear border between the area serviced by the unit package, and a room or part of a room. Zone is a random selection of the design engineer and air handling packages are available in a very wide range of sizes to cope with such load range. By definition, all such instruments, domestic air-conditioners, and are divided into three classes:
- Self-sufficient, where all the components of the refrigerant circuit are an integral part of the device. If not specifically stated, it is assumed that the air-cooled, i.e. with built-in air-cooled condenser.
- Water-cooled, with integral water-cooled condenser.
- Divide, given the condenser, remote from the air handling section, and connected to it refrigeration piping. The compressor can be in any section.
The size of the packaged unit will be limited to installation restrictions, as in the processing of the parts and the amount of air through the condenser. Units up to 50 kW of cooling capacity are in common use. Management of the internal condition of the cooling will thermostat in reverse airflow and thus based on the number of the dry bulb temperature.
As a result of the humidity level will depend on the coils characteristics and air consumption. Packaged air conditioners for tropical applications usually have a coil design sensible/General attitude of the order of 0.7 with air inlet 50% saturation, and give indoor conditions closer 45% saturation, if it is used in the climatic conditions with a temperature less than the latent load.
In winter, the heating elements are installed within the room air-conditioners can be an electrical resistance of elements, hot water or steam coils, or reverse cycle heat pump. In one model with water cooling unit operates with a condenser water temperature high enough to be used in the heating coil.
Heat return of the modular system consists of a water-cooled room units with reverse-cycle valves in the refrigeration circuits. Water circuit is maintained on 21-26C, and can be used as a heat source or sink depending on individual heating or cooling.
If the water circuit temperature rises above 26C, cooling towers, effective for deviations balance. If the circuit falls below 21C, heat is taken from the boiler or other heat source to compensate for the lack. In the middle of the season of work in a large installation, many blocks can be cooling and many heating, so that the energy rejected by the former can be used for the latter. With the correct configuration of the system, the use of the boiler and the tower can be minimized...
|
Air-Conditioning