In the early days of refrigerant recovery equipment, some contractors built their own units from spare parts on the shop floor.

When Environmental Protection Agency (EPA) regulations set minimum standards for recovery units, the market was suddenly flooded with minimum standard units. They may not have been able to recover a whole lot of refrigerant very quickly, but they looked good in service vans should EPA inspectors ever stick their heads inside to have a look.

But after an initial influx of manufacturers turning out recovery machines, the hvacr industry settled down to about a dozen or so respected companies turning out machines of increasing efficiency, reliability, and portability.

Each generation of equipment revealed technological innovations. One example of such innovation comes from Bacharach, who manufactures and markets SmarTec™ — billed as “the most advanced liquid refrigerant analyzer on the market.”

SmarTec was originally developed by Abilene, TX-based Analytical Index Technologies Inc. (AIT) and the University

of Alabama Automation and Robotics Department in Huntsville, AL.


“This is a product that can test and classify pure as well as binary refrigerants,” said Jon Gunyon, AIT director of engineering and development.

“Using refractive index measurement techniques, patented chamber, and state-of-art electronics, it is a step beyond non-disperse infrared technologies. Measuring refrigerant gases in their liquid state enhances accuracy, and its one-step analysis obtains results in seconds.

“The method and apparatus for the characterization of transparent fluids is based on the physical property of refractive index, correlated to temperature and pressure. By using these three variables, this microprocessor-based physical sampling apparatus characterizes refrigerants and discriminates them from one another to within EPA standards of 0.5% purity.”

Information from AIT noted that such refrigerants as 11, 12, 22, 113, 114, 115, 134a, 152a, 600 (butane), and 1301 (halon) are “indexed and classified to 99.5%.” Refrigerants that are “indexed and classified to within 2%” are 401A, 401B, 402A, 402B, 404A, 404B, 408A, 408B, 409A, 409B, 414B, 500, 501, and 502.

“The current instrument can characterize any fluid which is transparent with refractive index (RT) ranging from 1.15000 to 1.4000 ±0.00002 and vapor pressures up to 350 psia,” said Gunyon. He contended that “the technology incorporated into the instrument for making refractive index measurement is extremely reliable, since it requires no moving parts. Utilization of a laser light source and photo diode array provides an extremely accurate RI measurement and allows the instrument to obtain a resolution of 0.00002 RI units using advanced digital processing of the refracted beam.”

The SmarTec device is portable in design and available with a carrying case. It offers a variety of options for the technician. Using the onboard microprocessor, the basic unit in the standalone mode identifies any six gases. In addition, it can be upgraded for use with a greater library of gases.

For more information, contact Bacharach at 800-736-4666 or

Publication date: 05/06/2002