Drastic temperature reductions are used to prevent food from spoiling, but the cooling mechanism requires control in order to maintain the contents of the storage unit properly. Whether those contents are frozen or cooled, the freshly stored food must be maintained by the correct freezer and coolroom temperature management system.
Frosty Sub-zero Temperature Control
A frozen environment is one that’s locked at a negative value on the centigrade scale. The air is cooled by powerful compressors and sent through vents to freeze the cellular structure of the food, sealing in the flavour. The temperature typically drops to a frosty -10°C but can sink to -25°C on demand. Although this isn’t a scientific domain, a freezer that mandates split-degree temperature management, it’s still imperative that the food remains frozen if the biological state of the food, especially meat, is to be kept safely interred. Bacterial growth is therefore completely negated and quality preserved. And, since quality typically equates to freshness, the taste of the food is preserved, stored in this frigid state for months if necessary. This configuration benefits the long term storage of bulk items but isn’t suitable for moist fruit or dairy produce. Also, more energy is required for a commercial freezer, so keep this in mind when making space calculations for the unit.
Mastering Coolroom Temperature Management
The supervision of a freezer and coolroom temperature controlled environment is a complex issue, one that requires precise monitoring and superior thermostats. In the case of coolrooms, the ambient environment rises above freezing point, so liquids and creams can be stored without risk of damage. Consequently, meat and produce is kept cool but not so cool that the delicate cellular structure of the food crystallizes. Spoilage delay is relatively less effective when compared with freezing, but freshness is guaranteed in the short term due to microorganism retardation and a near complete cessation of enzyme action. Temperatures in commercial coolers bottom out above freezing point and peak at 5°C. Again, this range must be rigidly maintained by the compressor and the thermostat. Of course, as any energy audit inform us, subtle temperature variations also owe their presence to poor insulation and badly installed door seals, practices that are eliminated by professional storage solutions.
Time and safe food management top the refrigeration chart, but flavour and freshness come a very close second. Optimal management of temperature curves reinforce this ethic, keeping freezer and coolroom temperature governance firmly in the hands of coolroom installer experts.
Heating cables are a special form of electrical wiring that’s designed to radiate warmth. The product is flexible, so it’s quite easy to coil the cables around surfaces in order to keep them warm. Commonly used to defrost rooftops and gutters that are weighed down by snow, the purpose of the product takes on a sharper focus when used in freezers and coolrooms.
We imagine one environment when picturing freezers. A thermostat and a cooling unit drop the temperature. Ice forms, and heating requirements never enter our thoughts. This is a place that’s meant to be cold, after all. Subzero air stops taste-degrading biological processes, as intended, by keeping the climate frosty, but freezers and coolrooms also run on equipment and structural components that can’t cope with ice. The solution to the issue is special flexible heating elements, heating cables that act as a low-grade but effective trace warming line. They’re fitted to freezer doors to stop the ice from warping or freezing the mechanism, and they’re also used to protect pipes, as they run parallel to water lines, preventing liquid water from turning to ice.
Prevents Floor Heave
If we were to pop inside an old cooler and see how it has survived the decades, we’d probably be shocked, for the floor has undergone a terrible transformation. It’s cracked and uneven, rising in some spots and dipping dangerously in others. Concrete flooring doesn’t react well to subzero temperatures, which is why some form of floor heating is essential if we’re to avoid this messy structural phenomenon. An expertly installed set of heating cables, passing through every square metre of the floor inside plastic tubes, stops the floor from freezing solid and the concrete from experiencing “heaving.” Remember, a frozen floor will crack and lift, which presents a new avenue for energy loss. Heating cables pass through metal conduits or plastic pipes under the floor to counter this freezing threat.
The cables come in two related variants, known in the trade as self-regulating and constant wattage. The two conductors in the self-regulating type sandwich a special conductive core within the cable, and this core varies its conductivity as the temperature changes. Meanwhile, the function of the constant-wattage form is fairly self-explanatory, in that it delivers the same heat at all times.
An installation engineer considers the length of the run, the type of heating cables, and many other factors when adding heating to freezers and coolrooms.
Two critical variables govern the running of coolrooms. A highly efficient active cooling unit serves as the first half of the solution, but what about the passive half of the formula? All the cooling technology in the world will be next to useless without proper insulation, a physical layer that prevents heat from destroying the uniformly cool environment created by the cooling device.
What we’ve got so far is a vague notion of how coolrooms rely on a mechanism of some kind, a device that drops the temperature to near or below subzero values. The coolroom keeps the temperature at or slightly above 0°C. The walk-in freezer drops the climate far below this point, so low that the moisture in the air turns to ice and the enzymes in the food stop their chemical reactions, thus preserving the food from spoiling. This is basic coolroom science, with the actual coolrooms just using less cooling energy so that the food can still be handled and prepared for cooking, but uniformity is still a huge factor in both scenarios. Insulation stops heat from entering the room, a process some perceive as cold leaving the cooler. Therefore, the thermal isolating properties of the insulant, by simple logical deduction, can be perceived as a barrier, and, as such, are a crucial part of the cooling environment. In other words, the material maintains temperature by the blocking losses caused by external factors.
As with any other high-end passive material, when we improve the material design, its physical properties and/or dimensions, we enhance functionality. In the case of coolroom insulation, the material must cover every exposed square metre of open wall, but this isn’t enough. Thermal leakage is a surprisingly potent force, one that expresses its costs in spoilt food and high energy expenditure. Every corner and crevice must be evenly lined. Energy audits are then conducted on a regular basis to ensure uniformity is protected. The effect of such attentive monitoring and careful application of thermal insulation is invariably well-preserved food, typically to within a degree of that stated on the thermostat. Also, almost as importantly from a profit standpoint, electrical energy costs are significantly reduced.
An entire branch of industry is dedicated toward servicing coolroom insulation. New models come standard with modular polyurethane panels to maintain 100% energy efficiency. Meanwhile, older glass fibre and CFC-laden linings are replaced on a daily basis in a determined effort to push older models towards contemporary cooling standards.
C&M Coolrooms can create a custom solution for your specific needs. Talk to one of team members today.