When a typical refrigeration unit is cycling on about eight times every hour and holding temperature, contractors are a pretty happy lot. But what if the same unit only cycles on every two hours or so and still holds temperature? That could well mean low energy usage and much longer equipment life, meaning lower initial and long-term costs.

Mike Reihl, president of Reihl-Efficient LLC, thinks he has come up with a better mousetrap. His tweaking of an evaporator coil has been studied by Mid-Michigan Community College’s HVACR program to verify performance data.

“I was just looking at more efficient ways to do refrigeration,” said Reihl, who is working on the project in his spare time while working for a mason contractor. “I looked at a lot of potential ideas and played around on the Internet.” The effort took four years from the inception of Reihl’s first idea to developing the current prototype.


Reihl focused on a couple of main objectives: Designing an evaporator coil that is less expensive to manufacture and saving energy without sacrificing performance. For the prototype, Reihl’s coil replaced a standard one in a two-door commercial undercounter reach-in running on R-404A. A separate fan was then used. “The unit produces more cold than is needed,” he said. “So I’m harvesting that cold and reusing it. When the cabinet needs cold, the fan kicks in and pulls cold from the coil.” In addition to the less frequent cycling, Reihl said the unit is running on 30.4 kW a month, whereas the same system before the retrofit was running at 140.4 kW per month, more than four times the wattage of Reihl’s design. Additionally, Reihl said the anticipated manufacturing cost should be approximately one-third of existing designs.

Central Michigan University in Mount Pleasant, Mich., is involved in the business planning and marketing of the product. He also said the technology has drawn the interest of state officials who are looking at such technology as part of various Michigan green initiatives.

Now that the comparison testing has been completed, Reihl is planning on marketing the product to be sold or licensed to the manufacturing sector.

For more information, Reihl can be reached at 989-620-5396.

Publication Date:01/12/2009