Who Is Switching to CO₂ (R744)?
Integrating CO₂ as a refrigerant is a hot topic within the RAC and automotive industries and will also play a key role in addressing the increasing amount of environmental legislation aimed at eliminating the use of fluorocarbon-based cooling systems. Here is an overview of what’s happening across the industry segments – and a look at a number of refrigerant leak detection solutions.

• Mobile air conditioning
  Despite some debate about which substance will replace the current R134a as a refrigerant in automobile air conditioners, broad industry and regulatory support already exists for CO₂. A mobile system using CO₂ requires significant design changes to handle the high operating pressures (up to 120 bar / atm) needed for CO₂ cooling. An added advantage: CO₂-based air conditioners may be used for heating in the winter. Both Japanese and German mobile air conditioning suppliers are well advanced in their efforts to produce the appropriate systems, while Korea and the U.S.A. remain undecided.
  
  
• Commercial Refrigeration
  Already widely used in cascaded systems in combination with ammonia (NH₃), where large freezing systems are the norm – such as in supermarkets and food processing – CO₂ is also well-suited for deep freezing and dry freezing applications. Coca-Cola, very familiar with bottle vending systems, has published a study underlining the energy efficiency gains of CO₂-based beverage refrigerators. Further applications, such as cargo refrigeration also use CO₂ systems.
  
  
• Domestic Refrigeration
  The home market is still a relatively new area for CO₂ systems. The Coca- Cola study confirmed that the technology works, with the same benefits for beverage cooling applicable to home refrigerators.
  
  
• Compressors
  Used in refrigeration or air conditioning systems that run on CO₂, these compressors are already available and a major component that determine how quickly manufacturers of RAC products are able to switch to CO₂ as a refrigerant.
  
  
• Heating
  In general, many heat pumps (including CO₂ and conventional models) can be used for both cooling and heating, and are widely available, with large-scale models (for hotels, hospitals, etc.) now coming online. 70% of all heat pumps are installed in the U.S.A. and Japan, with the 3rd largest market in Sweden. CO₂ heat pumps are widely used in Japan for hot water production in private households, but are still fairly new to other markets.

Aiding innovation with advanced tools
Advances in leak detection technology enable manufacturers to improve efficiency and produce more reliable products in plants around the world. Because of differing production / testing environments and customer requirements, INFICON offers a wide range of leak detector products for different stages of the manufacturing process:

• HLD5000 – for CO₂; used in the final production / assembly testing of mobile air conditioners, domestic and commercial refrigeration, heat pumps and compressors
• D-TEK Select – for CO₂; optimized for service applications and also used for commercial refrigeration, where assembly (and leak testing) takes place on-site. Component and pre-assembly testing may be conducted with helium (just as for any other refrigerant)
• Protec P3000 / Protec P3000XL – specifically designed for full-time helium sniffing applications of components and pre-assemblies in demanding production environments
• LDS 2010 – a modular helium leak detector ideal for component testing with unmatched repeatability and minimal maintenance
• Modul1000 – a compact helium leak detector that is easily integrated into industrial leak testing systems (vacuum or sniffer mode)