R-410A, the Refrigerant of Choice
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In a concerted effort to be environmentally friendly, manufacturers of HVAC equipment are turning to chlorine-free refrigerants. With the phase-out of R-22 quickly approaching, several questions have been raised regarding which alternate refrigerant would be the best solution Specific Systems products. For Specific Systems and most other companies, this means a conversion of current equipment from R-22 to the higher pressure, more efficient R-410A refrigerant.
Montreal Protocol
In 1989, many of the world’s nations met to discuss production and consumption of ozone-depleting substances. Many of these substances were refrigerants that were classified as hazardous to the atmosphere, and the nations agreed to set deadlines for ending the production of these substances and any products that use them. Figure 1 shows the schedule for production phaseout of R-22, one of the most common refrigerants impacted by the Montreal Protocol and further national measures, such as the United States Clean Air Act.
R-22 is a HCFC (hydrochlorofluorocarbon) refrigerant. These HCFC refrigerants contain chlorine that has been shown to contribute to the ozone depletion. Because of these findings, governments worldwide have recommended or required the production of R-22 to cease entirely by January 1, 2020, with a significant reduction on January 1, 2010. Specific Systems has completely stopped production on new R-22 units to comply with the mandated change. EPA.gov states:
All developed (i.e., non-Article 5) countries that are Parties to the Montreal Protocol are subject to caps on their consumption and production of hydrochlorofluorocarbons (HCFCs).
Consumption is calculated by the following formula: consumption = production plus imports minus exports. The cap is set at 2.8% of that country’s 1989 chlorofluorocarbon consumption + 100% of that country’s 1989 HCFC consumption. The cap on production is set at the average of a) 1989 HCFC production + 2.8% of 1989 CFC production and b) 1989 HCFC consumption + 2.8% of 1989 CFC consumption. (Quantities of chemicals measured under the cap are ODP-weighted, which means that each chemical’s relative contribution to ozone depletion is taken into account.)
Prices for R-22 and other HCFC refrigerants are expected to increase as the final January 1, 2020 deadline for HCFC production approaches and supplies become limited. Production of HCFCs was reduced substantially in 2004, as it was lowered to 65% of production from the year 2000. However, as supplies of HCFC refrigerants decrease, refrigerant manufacturers will increase production on HFC (hydrofluorocarbon) refrigerants like R-410A. By taking advantage of new technologies like R-410A, companies have the added value of a product that will have continued availability in the future.
R-22 alternatives
Aside from R-410A, three refrigerants have had consideration; R-407C, R-417A/B, and R-422A/B/C/D. Two of these refrigerant blends, R-417A/B and R422A/B/C/D, which claim to be direct R-22 replacements and can be used in retrofit applications without changing any components or oils, have both been discounted by compressor manufacturers Emerson Climate Control (Copeland) and Bristol Compressors. The use of these refrigerants may void the compressor manufacturer’s warranty and therefore will not be considered as a standard replacement refrigerant by Specific Systems.
The third consideration, R-407C, has been used successfully for years in commercial air conditioning and refrigeration products, and is approved for use by all compressor manufacturers. This refrigerant, while providing acceptable performance early in the development of HFC alternate refrigerants, has very specific properties that are not suited to the wide variety of operating conditions that the Specific Systems product line may encounter. If operating in a range where fractionation can occur, a loss in performance as much as 15% can be expected. This could be unacceptable in critical applications.
Emerson Climate Technologies, the leading supplier of refrigerant compressors, released a publication that outlines some of the properties and unique characteristics of each of these refrigerants, and has clearly established R-410A as the best choice when considering alternate refrigerants.
How is R-410a different?
R-410A, an HFC (hydrofluorocarbon), represents the new industry standard in commercial and residential refrigerants, and is substantially more efficient than older, out-dated HCFC refrigerants. New technology breeds other new technologies, and the compressors for R-410A are smaller and more efficient than their R-22 counterparts. Additionally, we are working to provide other lighter components to take even better advantage of R-410A’s capabilities.
R-410A requires a higher pressure (between 50 and 70%, dependent on components) to operate, and in comparison to R-22, these pressures are much higher on both the high and low side of the circuit. For the product manufacturer, this means ensuring that all refrigerant lines are capable of withstanding much higher pressures.
Along with the higher pressure come greater efficiencies, as R-410A has greater thermodynamic capabilities than R-22. Essentially, the blend of HFC-35 and HFC-120 that comprises R-410A is better able to transfer heat than other refrigerants.
R-410A is incompatible with mineral oil commonly used to lubricate compressors. Instead, systems using R-410A refrigerant use synthetic polyol ester (POE) oil. POE oil is hydroscopic, so servicing technicians must be careful to abstain from exposing the system to air in order to avoid contaminating the oil with water vapor. As long as manufacturer’s instructions are heeded, this poses no risk to the equipment.
R-410A also is rated lowest of the alternatives regarding global warming potential (GWP) according to the ASHRAE Handbook 2006, as compared using the Total Equivalent Warming Impact (TEWI) index. TEWI includes using efficiency as a measure. Because of this, efficient refrigerants will contribute less to the TEWI, and R-410A has proven to be the most efficienct of the alternatives.
Specific Systems’ Commitment
R-410A has been used extensively in the United States since 1995, and the refrigerant has demonstrated itself to be the new industry leader.
Specific Systems tests each unit individually, and has reengineered each system to accept R-410A. Units using the refrigerant have been shipping, and current customers are pleased with the results R-410A systems have provided, even under harsh conditions.
Constant innovation drives the HVAC industry, and Specific Systems works to improve the products we provide to the industrial and process industries. We are excited about this transition, and take great pride in ensuring that our products exceed both regulations and your expectations.