When the sweet corn is brought in from the fields, the less-than-perfect ears are sorted out by hand and four dozen of the choice ears are loaded into each water-resistant box and sent down a conveyor belt through a tunnel that showers the corn with 36 degree F water being cooled by two 60-horsepower (hp) compressors.

It then emerges from the tunnel and makes a stop under an ice chute that fills the box with flaked ice. Two 60-hp R-502 semi-hermetic compressors and two eight-fan, 1.5-hp, air-cooled condensers support the ice machine. This system produces 120,000 pounds of flake ice per day under, at times, extreme conditions. The system is equipped with oil separators, four liquid receivers, and two suction accumulators.

"If we are not able to produce chilled water and ice, the operation comes to a standstill and losses mount up very quickly," said Hinkle.

An Alternative To R-502

The system has been well maintained and could have several more years of operation left in it - except for concerns about the rising cost of and supply questions about R-502. Because of these issues, Hinkle looked to his refrigeration contractor, Larry Bratton of Bratton's Heating, Air, and Refrigeration in Westville, Ill. Bratton, who has been in the HVACR industry since the early 1970s, has been maintaining Hinkle Produce's equipment since 1988.

"There have been times when I would be at this facility for 24 hours straight keeping these systems on-line," said Bratton. "But the fact is that if these systems are not running, thousands of dollars can be lost every hour. This is serious refrigeration, and I was very reluctant to convert this ice machine to any product that would require a lot of radical modifications."

He had heard about One Shot® (which is ICOR International's brand name for ASHRAE-designated R-422A). ICOR said its product is a nonozone depleting replacement for R-502.

When Hinkle's ice system went down for repairs at the beginning of August, Bratton recommended the use of One Shot for the conversion. He said it was chosen because it provides equal system capacity and would not require a POE oil change.

After the system was converted on Aug. 2, using approximately 3,000 pounds of One Shot, Bratton said system pressures were comparable to R-502, oil pressure and return were unchanged, and ice production was at full capacity.

For more information, contact icorinfo@icorinternational.com, or www.icorinternational.com.

Publication date: 10/03/2005