Advantages and disadvantages of air-conditioning water and multi-line fluorine

Advantages and disadvantages of air-conditioning water system and multi-line fluorine system

     I. Introduction of multi-line fluorine:

   There are two main types of multi-connection. One is to integrate the outdoor units of two to four household machines into one housing, and the refrigeration system and control part are independent of each other. They are generally used in homes and are not within the scope of this discussion. Inside.

   Multi-connection is an MDV system based on Japan's Daikin VRV and Copeland technology. The essence of these two systems is the same. One (one group) host can bring 1-16 (1-258) indoor units, Through variable flow technology, it can adapt to the difference in the number of indoor units turned on. Both of these two multi-line systems use the direct indoor circulation of the refrigerant, so the industry calls this system a fluorine system.

    II. Introduction to water system:

   Compared with the small central air conditioner of the fluorine system, the central air conditioner generally uses water as the medium for indoor circulation, so it is referred to as the water system in the industry.

   The central air conditioner of the water system is a comprehensive project, which requires special design. According to the different engineering conditions, the host can have a variety of choices. The common hosts include centrifuges, water-cooled screw machines, air-cooled screw machines, and air-cooled scrolls. Modular machines, etc.

   Third, the difference between the water system and the multi-line fluorine system:

   1. The operation of the water system is relatively stable

  Multi-line: The pipeline between the internal and external units of the multi-line system is refrigerant, and the heat exchange method is direct evaporation. Due to the complicated and frequent changes in the physical state of the refrigerant in the pipeline (liquid to gaseous/gaseous to liquid), it is easy to cause some rooms to be too cold while others are not cold enough.

  Water system: The pipes between the internal and external units of the water system are circulating chilled water, and the heat exchange method is secondary heat exchange. Since the heat transfer of water is relatively stable, the whole system runs relatively stable.

  2. The dehumidification of the water system is small and the human comfort is high

  If the household air conditioner is turned on for a long time, it is easy to feel dry mouth, mainly because the air conditioner is constantly dehumidifying, resulting in insufficient humidity in the room.

  Multi-line system: The direct evaporative heat exchange of the multi-line system and the household air conditioner are actually the same heat exchange method, which is easy to cause the indoor unit to dehumidify very strongly, and people are easily tired and uncomfortable when working in it.

  Water system: The secondary heat exchange of the water system, the indoor unit heat exchange type does not require excessive dehumidification, which can ensure a relatively suitable humidity in the room, and the human comfort is also very good.

  3. The water system is more energy efficient

  Multi-connection system: As long as the external machine is turned off in the multi-connection system, the indoor unit can no longer perform cooling or heating;

  Water system: Due to the lag in the heat transfer of water in the water system, the main engine should be turned off half an hour or an hour before get off work, only to ensure the circulation of the pump, which can meet the indoor needs.

  4. The water system is easy to find the fault point

  Multi-connection: Once there is a leak in the multi-connection system, the refrigerant in the entire system will all volatilize, affecting the use of the entire system, and the leak is difficult to find.

  Water system: If there is a leak in the water system, the water will not evaporate. It only needs to close the valve near the fault point for maintenance, without affecting the use of other parts.

  5. The water system is more suitable for larger office spaces

  Multi-connection: The main feature of the multi-connection system is that it is more energy-efficient when used indoors only below 50% of the room, but for office buildings, the daily use will basically reach more than 70%. In this case, multi-connection does not With the previous energy saving advantages. Generally speaking, buildings with an indoor area of less than 3,000 square meters can use multiple connections.

  Water system: After more than 3000 square meters, the water machine is more suitable in all aspects.

   IV. Summary of advantages and disadvantages of multi-line fluorine system and water system

  a. Advantages of multi-line fluorine system:

  1. The indoor air is cooled by direct evaporation of refrigerant, which has high efficiency and rapid response in cooling and heating time.

  2. There is no need to set up another air-conditioning room, the outdoor unit can be placed on the roof or on the ground, saving a lot of limited construction area, can save the basement for parking, and do not need cooling towers, circulating water pumps, softening Water and other cumbersome auxiliary equipment, equipment management and maintenance are significantly reduced.

  3. No need for special personnel to manage. Easy to install, because the connection pipeline of indoor and outdoor units is simple and does not require an air-conditioning room and a large number of auxiliary equipment, so the installation cycle is short. Each room is independently controlled.

  b. Disadvantages of multi-line fluorine system:

  1. High cost. The maintenance cost is high, because a new type of mixed refrigerant is currently used. If the refrigerant leaks, it is difficult to find the leak point, and all the refrigerant needs to be drained and then evacuated before refilling. The unit price of the refrigerant is generally 100-300 Yuan/kg, only the material cost will be 10,000 yuan.

  2. The installation drop between the indoor unit and the outdoor unit cannot exceed 50 meters, and the long distance of the piping cannot exceed 150 meters, which limits the scope of use.

  3. When heating in winter, it is greatly affected by the climate. In order to maintain the heating effect, the indoor unit is generally equipped with an auxiliary electric heater, which will be automatically put into use and increase energy consumption.

  5. Frequency conversion and multi-connection will produce electromagnetic pollution. Due to the low outlet air temperature and high dehumidification efficiency, the comfort is poor.

  c. Advantages of water system:

  1. Through the design, it can fully meet the comfort requirements, and the air temperature and humidity are relatively constant.

  2. The scope of application is wide, regardless of the size of the use area of machine room and air conditioner, there is a suitable host to choose.

  3. Centralized control and unified management. It can be stratified and measured by household.

  4. Compared with the fluorine system, the investment is small, the maintenance is simple, and the maintenance is convenient.

  c. Disadvantages of water system:

  1. The construction is complex and requires the cooperation of various majors.

  2. Some hosts require a dedicated computer room and special personnel are required.

  3. There are requirements for the quality of chilled water.