VRV Changed the History of Air Conditioning.
In the past, central air conditioning was the only way to air condition the buildings. Those were the days where hundreds of thousands of empty rooms around the world were unreasonably air conditioned.
Before development of the VRV multi-split air conditioner for commercial buildings, the design and installation of building air conditioning centered on selecting and integrating chillers, coils, fans, water circulation pumps, tanks, and instrumentation. In a totally new concept, Daikin developed the VRV to provide air conditioning using only of indoor and outdoor units. By greatly simplifying design and installation, Daikin revolutionized the world of air conditioning for commercial buildings.
Daikin incorporated inverters into VRV multi-split air conditioners for buildings to achieve capacity control from 0 to 100%. This resulted in operation that was neither excessive nor insufficient during partial load operation, which occupies the greater part of operation time. Consequently, both comfort and energy savings increased significantly. Furthermore, it became possible to connect indoor units of different capacities and then, select equipment that closely matched room size and conditions.
Depending on the location, there were cases when installation was not possible for air-cooled VRV because of refrigerant piping length. However, the appearance of water-cooled VRV allowed units to be flexibly arranged without limitations of refrigerant piping length. Individual air conditioning also became possible in large-scale buildings such as high-rise buildings. Because water-cooled type air conditioners do not require heat exchange with air, they can be installed in the closed environments of underground shopping areas and in cold climates where outdoor temperature is low. With the arrival of water-cooled VRV, the market of VRV has greatly expanded.
Daikin developed a unique refrigerant circuit that minutely regulates the refrigerant flow for both heating and cooling to achieve individual air conditioning even for buildings with both cooling and heating needs. Furthermore, the heat recovery operation utilizes exhaust heat during cooling operation and reuses it for heating to significantly increase energy savings. This achieved a comfortable indoor environment throughout the year by automatic change over between heating and cooling according to the set temperature.
In the late 1990's, air conditioning refrigerant shifted from R22 to R410a to protect the environment because R410a had a lower environmental impact than R22. The advance of air conditioners with low environmental impact matched the time VRV air conditioners using R22, which had been adopted 15 years earlier, were entering their replacement period. However, because of the large-scale installation involved, the shift did not go smoothly because of the required expense and time.
Seeing this, Daikin designed a method for reusing the existing piping by utilizing a thermally-driven secondary refrigeration system and filtering out Impurities in the refrigerant. This significantly reduced the man hours needed for replacing the VRV multi-split systems. Today Daikin has made further advancements and developed a system that automatically performs all steps from refrigerant charging to system testing. As a result, Daikin has achieved even greater reduction in labor hours needed for installation. Daikin's development greatly promotes the shift to new refrigerants and contributes to a lower environmental impact.
Conventionally, controlling humidity required a large amount of energy for reheating. For this reason, Daikin developed an air conditioning system with an individually treatment for latent and sensible heat, and this significantly reduced the air conditioner's work by removing latent heat. Using the heat pump as heat source, DESICA employs a heat pump desiccant method to efficiently adsorb and release moisture into the air. Because humidification and dehumidification are performed without supply and drain piping, this revolutionary system saves installation piping and the owner does not need to care for water quality.