At China Refrigeration Expo 2021 (CR 2021), a i r handling units (AHUs), fan coil units (FCUs), fans, air ducts, fresh air systems, etc. were exhibited on a considerable scale, focusing on healthy functions in the context of the pandemic. For example, filtration and sterilization functions have been added to conventional technology, and there were greater numbers of fresh air systems exhibited. In this report, automatic controls for buildings are also a key focus.
AHUs
At CR 2021, AHU models with clean air functions for the medical sector were a key focus.
TICA exhibited a cloud inverter heat recovery direct expansion (DX) type AHU with higher filtration efficiency and a smaller thermal bridge that complies with the TB1 class of thermal bridging in European standards. It recovers condensation heat for dehumidification and reheating, providing reheating air at a temperature of up to 15℃. Compared with conventional electric heating and reheating, the AHU achieves energy savings of up to 55%.
Siukonda exhibited a free heat recovery direct current (DC) inverter AHU with condensation heat recovery function for dehumidification and reheating. McQuay displayed the MDX-C inverter DX type AHU, which is suitable as an independent temperature and humidity control system. Trox showcased the X-CUBE X2 AHU with a patented two-way door structure that opens on the left and right sides or can be removed as a whole, making operation and maintenance of the unit easy in a small space.
The above-mentioned four AHUs won Innovation Product Awards during the expo.
FCUs
At CR 2021, there were many FCU models with filtration functions to purify return air supplied to rooms in the context of the pandemic.
TICA exhibited a healthy FCU featuring initial resistance of the highand medium-efficiency filtration modules that is lower than 22 Pa. McQuay and H&V also exhibited corresponding filter FCUs. Gree and Tongchuang exhibited purification FCUs based on the principle of plate-type electric dust removal and plasma purification. YORK and Gree showcased FCUs with new 360° air outlets.
Fresh Air Systems
In the context of the pandemic, fresh air systems were in the spotlight during CR 2021.
In addition to the functions of high-efficiency filtration, purification, and sterilization, a large number of enterprises have worked hard on the integrated performance of fresh air systems. Panasonic displayed its Six-Constant climatological station composed of an air conditioning module, a fresh air module, and a humidity control module. Dpurat Environmental Technology showcased a passive fresh air system for buildings that integrates cooling, heating, dehumidification, sanitary hot water production, fresh air replacement, and energy recovery functions.
New types of fresh air systems configurate electronically commutated (EC) fans as standard, realizing low noise and good regulation performance. Many manufacturers such as Holtop, Reborn, Dpurat, and Jev&Kev showcased new fresh air systems using EC fans.
Fresh air system manufacturers improved certain aspects of their products to ensure easy installation and maintenance. Some enterprises such as Reborn, Dpurat, Madelon, and Matsui improved the design of the openings, while others developed the thin and light-weight units that save installation space. Hyundai and Nanyo displayed ultra-thin fresh air systems that adopt total heat exchangers and clean the particulate matter with diameters of up to 2.5 micrometers (PM 2.5), and Madelon exhibited a compact fresh air system that can be repaired from the top and side.
Fans
At CR 2021, more than 40 fan manufacturers participated, and this was a greater number than in previous years. They displayed fans that were developed with a focus on high efficiency, low noise, etc. Greater numbers of fans with EC motors and a bionic blade structure design were displayed.
The EC fan for data center air conditioning from Changzhou Xiangming Intelligent Drive System won an Innovation Product Award in the fan category.
Air Ducts
Fabric air ducts have become a hotspot in the industry in recent years. Such ducts are used extensively in large spaces such as production plants and stadiums. More and more domestic companies have entered this emerging segment.
Durkeesox maintains a leading position in the fabric air duct segment. The company exhibited air ducts made of composite rubber-plastic thermal insulation material that won an Innovation Product Award, thanks to their excellent resistance against fire, ultraviolet (UV) rays, acids, alkalis, etc.
Prihoda has launched a product that can switch between side wall and bottom air supply modes. Mixi launched a plenum chamber with a fabric structure and a space-saving fabric duct with a semicircular cross-section.
Automatic Controls
As for automatic controls, intelligence, integration, and high efficiency were key themes at CR 2021.
Existing intelligent control has been further improved from control of individual heating, ventilation, and air conditioning (HVAC) systems to control of a whole building including power systems, fire protection systems, etc., and from the control of a single building to the control of the entire residential property. Continuous innovations and improvements in these areas have efficiently integrated modern information technology (IT), promoted the overall high efficiency and energy savings of buildings, and accelerated the pace of achieving the goal of carbon neutrality by 2060 in China. Danfoss introduced Internet of Things (IoT) air conditioning and refrigeration solutions to control different systems in different scenarios, including smart energy-saving systems, indoor environment monitoring systems, etc. for commercial buildings, data centers, etc.
Haier showcased a high-efficiency IoT solution for data centers that won an Innovation Product Award. The system integrates the air conditioning unit, a water pump, a cooling tower, etc. in one box, which not only saves space but also connects to the cloud platform through IoT and fifth-generation (5G) technologies. Each part of the equipment can realize self-networking, self-monitoring, and self-adaption, enabling stable operation and generating optimal operation without manpower.
Gree, Haier, etc. introduced smart building cloud platforms in the context of carbon neutrality. Unlike conventional centralized control systems, such platforms connect different brands of energy-consuming systems in buildings such as central air conditioning, lighting, and fire protection systems, and elevators, thereby providing real-time energy consumption data and outputting efficient solutions based on big data analysis. In addition, manufacturers such as Midea, Johnson Controls, SLHD, and Rikind have also developed a wide range of regional-level smart energy solutions to provide digitization from multiple dimensions such as people and vehicles, security, equipment, the environment, and energy consumption, enabling sharing of the information within the entire area, realizing of integrated and intelligent management, lowering of the overall energy consumption of the region, and contributing to regional energy savings and emissions reduction.
Note: This report is a summary by JARN based on ‘Air Handling Units and HVAC Automatic Control Systems’ in ‘Technical Summary of the 32nd China Refrigeration Expo 2021
