Good refrigeration performance and management help to keep food at the correct temperatures and minimize electricity costs for refrigeration. Store refrigeration systems require vigilance and maintenance for reliable and efficient operation. Every refrigerated case and walk-in should have an accurate thermometer that someone checks regularly. Ideally, an employee or manager should know how the system works, what the case temperatures should be, and the common signs of trouble.
Store policy should dictate that all refrigerated deliveries go immediately to refrigerated storage or refrigerated display. Food-quality and energy conservation both require fast loading after delivery, before the delivered food warms up. It pays to be organized about loading and unloading walk-ins, using carts and trays to limit trips in and out.
The ability of your refrigerators to maintain the correct temperature depends on sufficient product loading and adequate air circulation through the case by the evaporator fans. The most efficient display case is one that is fully loaded but that also has some space between the items to allow air circulation. Walk-in coolers and freezers also need spaces between racks and items. When cases are loaded too tightly, items on the top shelves become warmer than lower-loaded items, and the case uses around 5% more electricity. When cases are too lightly loaded, the system efficiency suffers from frequent cycling of the compressor.
Controlling moisture and humidity in your store is important for minimizing refrigeration costs, especially if you have open display cases. Southern California Edison’s refrigeration-research team reports that reducing store relative humidity from 55% to 35% reduced the refrigeration electrical load 18% and reduced coil icing 62%. Control moisture at its source by ventilating cook stoves and ovens and otherwise reducing the amount of water, evaporated into the store. In winter, adding outdoor air will reduce indoor relative humidity, but try to minimize ventilation and air leakage in summer. In summer, you may have to adjust your store’s air-conditioning system to remove moisture more effectively.
If you clean your coils when they need cleaning, a good refrigeration system should operate trouble-free. Some stores require a lot of service calls, and some stores require practically none. The difference is the quality of the equipment, installation, and control. Don’t let recurring problems damage your customer loyalty. If recurring problems plague your store, your best long-term option is to invest in a permanent solution, such as equipment replacement, system redesign, computerized monitoring and control, or even a complete system overhaul.