Contractors in the supermarket sector sometimes face a twofold challenge. They may be coming into a situation after the previous servicing company has left, only to discover a system of components seemingly pieced together without consideration of the best choices. Or, they may be entering into the equation with some new stores coming on line that just happen to have old-line technology.

Isn't there a way, these contractors ask, for those involved in supermarket mechanical systems to see to it that the right components are chosen and all options are considered?

A new breed of consultants hopes to be able to give a "yes" to those questions. Their job: to act as independent, neutral experts.

One such consultant is Emerson's Design Service Network. Program Manager Sean Orban noted that even though the Design Service Network is part of a company that has a range of products for supermarket refrigeration, the network offers options to those making decisions based on its own independent research, pricing, costing, and other data. It also relies on track records of similar projects already on line.

Those with a vested interest (usually engineers within a supermarket chain) make the final decisions. Orban said Design Service Network steps aside once the actual installation starts, although a few of its people may go out to see how the work is progressing.

More Options

Of special importance, he said, is the ability to give decision makers a wider range of options than the familiar choice of direct-expansion (DX) systems. There are certainly instances in which DX is the best choice. However, the supermarket segment has been offering other options for close to a decade now. Parallel rack manufacturers, for instance, have showed these options each spring at the Food Marketing Institute Expo in Chicago.

The arrival of consulting groups like Design Service Network gives the options more of a third-party perspective, in which pluses and minuses are researched and explained.

Bob Nash, senior engineer at Design Service Network, pointed out that consideration of one such option - secondary loop - was based on the consultancy's own testing and monitoring of operating systems. Nash contended that secondary loop offers a way to reduce refrigerant charges in a store and confine the refrigerant to a more isolated area. Secondary loop systems also allow for the use of fewer system components, allow for more simplified piping, increase evaporator capacity, achieve defrost with warm fluid through the discharge line, and use a single fluid that doesn't change phase from a liquid to a gas.

Secondary loop negatives, he said, include higher initial costs and higher maintenance costs. These factors could be reduced in the future through better understanding and increased use of the technology.

Nash said Design Service Network maintains neutrality on the question of what technology is best. He said the intention is to present all options and provide as much statistical and technical information as possible to those making the purchasing decisions.

What does this all mean to service contractors and technicians? Even if such individuals are not part of the pre-installation planning, hopefully they can be more assured that the supermarket systems they will deal with in the future will be systems based on an expanded base of knowledge, including that of independent voices.

If the technology goes beyond the familiar direct expansion, those new methods could well have been researched and documented.

Peter Powell is refrigeration editor. He can be reached at 847-622-7260, 847-622-7266 (fax), or

Publication date: 05/03/2004