7.94mm coil provides savings on raw material and refrigerant costs without sacrificing efficiency
(November 3, 2010). Luvata HTS North America has developed a new large face 7.94mm HVACR coil to increase heat transfer efficiency and allow customers to address recent changes in refrigerant regulations and usage. The new coil surface is capable of capturing the benefits of the superior heat transfer properties of R-410A, the new refrigerant of choice being widely used by commercial A/C and specialty HVACR equipment manufacturers.
The large face engineered 7.94mm copper tube coil, which is available in face sizes of up to 60” (60 tubes high) X 108”, offers smaller diameter tube and a more compact heat exchanger for enhanced performance in commercial applications. Luvata’s new design delivers high heat-transfer coefficient with improved performance in a longer length coil.
The large 7.94mm coil design utilizes a compact tube pattern, delivering savings on raw material and refrigerant costs to commercial A/C and specialty HVACR equipment manufacturers, without sacrificing efficiency.
“Recent changes in refrigerant use and regulations have caused equipment manufacturers to pursue new heat transfer solutions to optimize refrigerant charge while obtaining maximum efficiencies,” explains Dave Anderson, Vice-President Sales and Marketing with Luvata Grenada. “As a result, the characteristics of R-410A support the use of smaller tube diameters in heat exchangers, previously only available in smaller coil sizes.”
Historically the coil of choice for commercial and large tonnage HVACR applications has been 3/8” or 1/2” tube heat exchangers up to 40” X 96” finned lengths, but new refrigerants have led to a need for new coil surfaces that can capture their benefits.
Studies which compare R-410A with R-22 found that the evaporation heat-transfer coefficient of R-410A is 25% higher and the refrigerant pressure drop is around 30% lower than R-22. The condensation heat-transfer coefficient of R-410A is approximately 5% higher and the refrigerant pressure drop is around 30% lower than R-22. The resulting volumetric refrigerating effect of R-410A is about 1.6 times that of R-22.
With its flatter saturation temperature curve, R-410A can have a higher refrigerant pressure drop and maintain an equivalent saturation temperature change (dTsat) to R-22. When comparing R-410A and R-22 coil designs with identical capacity, change in refrigerant saturation temperature and the same number of circuits, the tube diameter could be reduced by 20% with R-410A. Matching the characteristics of R-410A with a smaller diameter tube and more compact coil surface delivers a highly efficient coil product with improved performance.
In addition to refrigerant optimization, the expanded use of heat pump technology in the commercial HVACR market is driving manufacturers to search for new solutions. Micro-channel products continue to gain support in this market for cooling only condenser applications, but currently fall short in applications where refrigerant distribution and condensate removal are a concern, including evaporators or outdoor coils on heat pump units.
The new 7.94mm design provides exceptional compatibility as a large evaporator being matched to Luvata’s Aluminum Microchannel condenser and outdoor heat pump applications where the coil operates both as condenser and evaporator in the reverse (heating) cycle.
Luvata is the leading international metals supplier of solutions, services, components and materials for manufacturing and construction. Luvata’s solutions are used in industries such as renewable energy, power generation, architecture, automotive, transport, medicine, air-conditioning, industrial refrigeration, consumer products and construction. The company’s continued success is attributed to its longevity, technological excellence and strategy of building partnerships beyond metals. Employing over 7,000 staff in 18 countries, Luvata works in partnership with customers such as Siemens, Toyota, CERN, Shaaz, and DWD International.
Luvata’s Heat Transfer Solutions division is the leading global manufacturer of finned pack heat exchangers, playing a prominent role in the design of air units for the air conditioning and refrigeration industry. With a prominent presence in America, Europe and Asia and plans for further expansion in emerging markets, Heat Transfer Solutions division is the reliable business partner for HVACR players worldwide.
For further information, please contact:
Dave Anderson, Vice-President Sales and Marketing
Luvata Grenada LLC
Tel: +662 229 2076