Central air conditioning cooling water system layout method

Central air conditioning cooling water system layout method

It is most suitable to choose central air-conditioning as refrigeration equipment in large spaces such as hotels and hospitals. However, the installation of central air conditioners is far more complicated than platform air conditioners. Detroit air-conditioning leasing professional technicians said that if the central air-conditioning installation, especially the central air-conditioning cooling water system layout, is not carefully considered, there will be big problems.

The circulating cooling water system of the central air conditioner is an open system. If the volume of the cooling tower catchment tray is small or the cooling tower is too far away from the water pump and the resistance balance of the cooling tower outlet pipes running in parallel is seriously out of balance, the air will be mixed into the water and enter the water pump. Pressed into the pipeline, causing serious water hammer, causing damage to the pump outlet pipe and its fittings.

　　 When choosing a cooling tower, you should first pay attention to the gap between the performance parameters given in the product sample and the actual performance of the product. Including factors such as the false product samples and the difference between the meteorological conditions of the project construction site and the test conditions of product calibration performance. It should be checked according to the meteorological conditions of the project site. And should take corresponding adjustment measures according to the engineering application experience of the product. Sometimes a larger margin factor has to be used.

　　 Cooling towers are generally installed on the skirts of high-rise buildings. Since it is close to the main building, the suction distance, fire prevention, noise, and fog of the cooling tower should be considered. The national regulations on the suction distance of cooling towers are specified in detail.

　　When choosing a cooling water pump, it should be decided according to the circulation resistance of the cooling water system, the water delivery height difference and the free head, and it is not suitable to be too rich. The flow rate of the water pump should be determined according to the temperature difference of the cold water after calibration. When multiple pumps work in parallel, calculation and verification should be performed according to the parallel curve. Can not blindly superimpose the water volume according to the number of units.

When cooling towers are used in parallel, the pipeline resistance is balanced, and the distance between the cooling tower and the pump should not be too far; the pump should be arranged in front of the chiller (that is, the cooling water is pressed into the chiller); and the pump should be self-filling; avoid pumping The suction pipe bends up and down. In addition, cooling pumps, chillers, and cooling towers should be in one-to-one correspondence to facilitate adjustment and flow balance. If the above control cannot be achieved, an automatic control system should be used. Solenoid valves should be installed at the inlet and outlet of the cooling tower, and Should be opened and closed simultaneously. Or set a balance valve on the inlet and outlet pipes of each cooling tower to ensure that the water intake of each cooling tower meets its rated flow. In order to increase the water collection capacity of the suction pipe, the diameter of the suction pipe can be appropriately increased when designing the suction pipe .

　　 Regarding the collection pool of the cooling water system, in the past when designing cooling water equipment, the volume of the collection pool was mostly set at 10% of the cooling water volume (see the air conditioning refrigeration manual). This requirement is no longer applicable when selecting water-collecting cooling towers. Water-collecting cooling towers have their own water collecting tanks, which have a small capacity, but it has been proved to be able to meet the needs of cooling water pumps. The current air-conditioning cooling water system is limited by construction conditions, and most of them cannot be installed with large-scale water collection systems that meet the 10% cooling water requirements. Therefore, rely on the water collection tank of the cooling tower itself and do a good job of maintaining the water level and making up water. Relevant materials recommend that the volume of the water collection tank is generally 2% to 3% of the cooling water volume. The building conditions permit the addition of a pool, and its capacity should not be too large, and it does not need to be set at 10% of the cooling water volume. As long as the water volume of the cooling water system can be accommodated, the normal starting and working of the cooling water pump can be ensured.