How Your Reach-in Works

Making Sense of Reach-in Refrigerator Jargon

If you've talked to a salesperson or a service technician about your reach-in refrigerator, you've likely heard of things like the "evaporator fan," "capillary tube," and "temperature recovery." These technical terms probably concern you less than the longevity and durability of your major commercial equipment. However, with a few key terms in your vocabulary, you can care for your equipment better, avoiding costly breakdowns and service calls.

Any refrigerator must remove heat from its insulated cabinet and bring temperatures below 41 degrees Fahrenheit to slow the growth of bacteria in food, extending the time it can be kept safe to eat. Below, you can learn more about individual components and how they work together to cool product.

Refrigerant

Refrigerant – the substance that circulates through the system – carries heat from inside the cabinet to the air outside. Historically, several different chemicals have been used as refrigerant. You may hear any or all of them referred to generically as "Freon," but that word is a trade name for several refrigerants made by the Chemours company, which spun off from Dupont in 2015. Refrigerants are officially named with a system that prefixes each type with an "R" – R134 and R290, for example.

Most traditional refrigerants are manmade, lighter-than-air chemicals composed of hydrogen, carbon, and a halogen gas or two such as chlorine and fluorine. The first major generation of refrigerants to be used widely in refrigeration equipment was comprised of CFCs (chlorofluorocarbons) like R12 and R22. All CFC molecules contain chlorine and were found to damage the Earth's ozone layer when released into the atmosphere. As a result, CFC refrigerants were phased out in the United States during the 1990s and early 2000s for most non-industrial applications.

The chemicals designated to replace CFCs are known as HFCs (hydrofluorocarbons). HFCs like R134A and R404A contain hydrogen in place of CFCs such as chlorine, which means they don't have the same ozone-damage potential as their predecessors. Unfortunately, HFCs were discovered to be powerful greenhouse gases that can trap thousands of times more heat in the atmosphere per volume than carbon dioxide. For that reason, the United States government announced in 2015 that foodservice equipment manufacturers must phase out HFC refrigerants from most of their products by 2019.

The EPA-approved refrigerant that most manufacturers have chosen is R290, which is a form of propane, the common fossil fuel that powers the grills and mobile heaters we're all familiar with. Unlike its synthetic predecessors, R290 refrigerant has no potential to deplete the ozone layer and contributes hundreds of times less to global warming. Its molecular structure consists of only hydrogen and carbon – hence why it's sometimes referred to as a "hydrocarbon refrigerant."

The move to hydrocarbon refrigerant has benefits beyond environmental protection. Equipment designed for R290 refrigerant operates at a lower pressure than its predecessors, so it's likely to provide longer equipment life because it puts less wear and tear on refrigeration components. Equipment that uses hydrocarbon refrigerant can be more energy efficient than traditional equipment, so operators who switch to hydrocarbon equipment are likely to save on their utility bills.

The Condensing Unit

The term "condensing unit" describes a group of components including a reach-in refrigerator's compressor and condenser coil, which are always located on the outside of a commercial reach-in refrigerator's cabinet. The compressor is a mechanical component that drives refrigerant through the reach-in refrigerator's system. It's named for its role in compressing refrigerant, changing the substance from a gas to a liquid and priming it to release its stored heat.

Once it's been compressed, refrigerant passes through a long, thin, winding copper tube known as the condensing coil. The copper tubing is surrounded by hundreds of tiny fins that draw heat away from the refrigerant. The condenser provides a wide surface to transfer the refrigerant's heat into the surrounding air, and a fan blows air over the coil for further efficiency.

Condensing Unit Location

Another concept you're likely to encounter when exploring your commercial reach-in refrigerator options is top-mounted vs. bottom-mounted condensing units. We cover this topic in depth in our top- vs. bottom-mounted condensing unit article, but we'll list the major advantages of each here.

In bottom-mounted reach-in refrigerators:

  • Components are accessible for cleaning and maintenance.
  • The condenser operates away from higher temperatures near the ceiling.
  • Components are less likely to be affected by greasy air that migrates toward the ceiling.

In top-mounted reach-in refrigerators:

  • Components aren't exposed to dirt and dust on the kitchen floor.
  • Heat from the reach-in condenser doesn't rise into the cabinet.
  • More cabinet space can be dedicated to holding products.

The Evaporator

The counterpart to the condensing coil is the evaporator coil, which is always located in the top of the unit. Like the condenser, the evaporator is comprised of a long, winding tube that enables the refrigerant to absorb heat from the commercial reach-in refrigerator's cabinet. Refrigerant is in a gaseous state while it's in the evaporator, and the evaporator fan blows air over the coil, so it cools the cabinet evenly and efficiently.

As the reach-in refrigerator's evaporator pulls heat out of the air in your refrigerator's cabinet, it causes moisture in that air to condense into liquid water. Because the evaporator coil temperature is below freezing, that liquid water will turn into ice. To prevent the resulting ice from building up so much that your equipment encounters problems, the system will periodically enter a defrost mode.

Manufacturers employ several different methods to defrost the evaporator coils. One of the most common is the hot gas defrost system, which reverses the refrigeration cycle so that the evaporator coil warms up, melting the ice that has collected there. An alternative to the hot gas cycle is the electronic evaporator heater, which melts ice with an electric heating element attached to the evaporator coil. Hot gas systems take less time and electricity, but they put extra stress on the refrigeration system by heating the coil very quickly, possibly shortening the equipment's life.

Manufacturers sometimes describe their reach-in refrigerator's defrost systems as time-initiated, temperature-terminated. That phrase simply means that the defrost system starts automatically according to a timer and ends when the system has reached the proper temperature to melt all the ice that has collected. An alternative to this system is the time-initiated, time-terminated defrost cycle. This simpler system is usually less expensive upfront but can cause the defrost cycle to last longer than necessary, wasting electricity.

Of course, manufacturers must also include some method to handle the water that results from the defrost process. That water is generally piped into a condensate pan underneath the refrigerator, where a heating element encourages it to evaporate. These systems are often coupled with wick systems designed to expose the water to air, speeding up evaporation.

A commercial refrigerator will enter its defrost mode automatically, usually three or four times a day. Many refrigerators also include manual defrost modes, but those are only needed while the equipment is being serviced. If you feel that your commercial reach-in refrigerator is entering its defrost mode too frequently or infrequently, consult a service technician, who can adjust the defrost timer for more efficient performance.

Capillary Tubes vs. Expansion Valves

Every reach-in refrigerator must include a mechanism that meters the amount of refrigerant that flows into the evaporator coil. This mechanism ensures the refrigerant can absorb heat efficiently. Two types of metering device exist for this purpose.

The capillary tube is the simplest type of metering device, and refrigerators built with them tend to be the most affordable. A capillary tube is a thin tube that meters refrigerant by responding to pressure changes within the system. Reach-in refrigerators with capillary tubes can maintain steady temperatures but can struggle bringing down warmer product temperatures. For that reason, commercial reach-in refrigerators with capillary tube systems should only be loaded with product that's already at the proper temperature, such as those that you transfer from a walk-in cooler.

Thermal expansion valve systems – often abbreviated TXV – are more sophisticated, capable of responding to changing conditions, and can bring room-temperature products down to holding temperatures. For this reason, many industry experts recommended an expansion-valve reach-in refrigerator when an operator needs a "working box" – that is, a reach-in refrigerator that'll be accessed frequently in high-demand areas, such as the hearts of commercial kitchens.

Insulation

Look at the specs for virtually any commercial reach-in refrigerator and you're likely to see the words "foamed in place" to describe the insulation. This term describes how insulation is blown into the equipment's cabinet from a pressurized chamber, forming a dense, rigid mass that prevents heat from passing through the reach-in refrigerator's walls.

A well-insulated cabinet minimizes runtime for the refrigeration system, saving energy and keeping your reach-in refrigerator longer in service. Another benefit to good insulation is that it reinforces the cabinet's structure. Thick insulation can protect the commercial reach-in refrigerator's cabinet from dents and dings, and keep the frame from sagging so doors and other essential structural components continue to fit for the life of the reach-in refrigerator.

Reach-in Refrigerator Temperature Recovery

"Recovery" is a commercial reach-in refrigerator's ability to bring its cabinet temperature back to the set point after an event occurs that introduces heat into the cabinet, such as the door being opened or someone placing room-temperature food into the cabinet. A reach-in refrigerator that has good recovery will bring the cabinet back to the correct temperature in a short amount of time.

For equipment to keep food safe from the microorganisms that cause foodborne illnesses, it must reduce the time interior temperatures are in the "danger zone" between 41 and 139 degrees Fahrenheit. Equipment with poor recovery may cause food to drift into that range, enabling pathogens to develop and affecting the safety and quality of food.

Another benefit of quick temperature recovery is that the reach-in refrigerator won't run for an excessive period. Shorter run times translate to lower energy consumption and reduced wear and tear, so your commercial reach-in refrigerator is likely to last longer and require fewer service calls over its lifetime.

The Importance of Maintaining a Clean Reach-in Refrigerator

If you maintain your reach-in refrigerator, it should continue to serve you for years without needing many service calls. A commercial reach-in refrigerator that's bogged down with grease and dust must run harder to reach the right temperature, wasting energy and risking a breakdown when the strain becomes too much for the system to handle.

A single service call can cost hundreds of dollars, not to mention the added cost of part replacement. To reduce service calls, perform the following maintenance chores periodically. For a full list, see our guide to commercial refrigerator maintenance.

  • Keep the condensing coil clean. Since the condensing coil is responsible for eliminating heat, it must be kept clear of dust in order to do its job. Maintaining a clean reach-in condenser is necessary to keep your warranty intact. If your reach-in refrigerator is using too much electricity or isn't getting cold enough, you should clean the coils, preferably once a month. First, unplug the equipment. The food inside will remain safe if the door is kept shut and is at the right holding temperature. Then, remove the grill and clean the coils with a coil brush. A vacuum cleaner crevice attachment will remove smaller particles, but you should avoid bending the fins on the coil. Afterward, reinstall the grill.
  • Clean the cabinet. Keeping your reach-in refrigerator's cabinet clean, inside and out, will prevent it from rusting and pitting, potentially extending its lifespan. Not only that, but you'll protect your customers by eliminating bacteria that could potentially contaminate food held in and near your refrigerator. Make sure to use the appropriate cleaner for the surface you're cleaning. Exposing certain metals to harsh chemicals can do more harm than good.
  • Check the gaskets for wear and tear. Your commercial reach-in refrigerator's gaskets are responsible for sealing warm air out of the cabinet. Over time, they can become worn, loose, or cracked, enabling warm air to seep in from outside and forcing the reach-in refrigerator to work harder than necessary to keep the equipment cool. A popular test of a gasket's quality involves closing the door with a dollar bill between the gasket and the cooler. If the dollar falls out, the gasket has become worn and should be replaced. Follow the reach-in refrigerator manufacturer's specifications for cleaning and lubricating the gasket to keep it in service for longer.

Which Doors Should Your Reach-in Have?

Commercial reach-in refrigerators are also available in different door configurations, such as solid or glass designs. The former is simpler to clean and provides more insulation, while the latter is ideal for product accessibility and visibility, which reduce door holding times and keep cold air in the unit.

Glass door reach-in refrigerators shouldn't be mistaken for glass door merchandisers, which are only safe for holding prepackaged, nonhazardous goods such as cans and bottles. These merchandisers are constructed for front-of-house use because they can't withstand ambient temperatures above 75 degrees Fahrenheit. Glass door reach-in refrigerators, in contrast, can be used in the back of house.

Commercial reach-in refrigerators are constructed with half-size or full-size doors. Half-door models are recommended for establishments that want to compartmentalize their products, conserving energy and regulating internal temperatures more consistently. They create top-shelf accessibility and enable one door section to be opened at a time. Conversely, when opening a full-size door, the entire opened side is exposed to kitchen temperatures. Because full-height door models don't have a middle separator in each section of the unit, they provide more storage space than half-height models.

Most reach-in refrigerators are designed with a swing door, which can stay open for loading and unloading product. Swing doors, however, can sometimes block traffic flow in narrow kitchen spaces. There are reach-in refrigerators available with sliding-door configurations, recommended for establishments with no space for a swinging door. However, sliding doors self-close and can make loading and unloading product more challenging.

Commercial reach-in refrigerators are available in one-, two-, and three-section models. In general, one-door reach-in refrigerators have an average capacity of 23 cubic feet, while two-door units measure 46 or 48 cubic feet. Three-door reach-in refrigerators usually have approximately 72 cubic feet. These measurements, however, all depend on the model and manufacturer. And while a larger commercial reach-in refrigerator will enable greater storage capacity, it'll also occupy more floor space and consume more energy.

Do Materials Make a Difference?

Reach-in refrigerator manufacturers employ several different materials to build their equipment. Specific combinations vary from manufacturer to manufacturer and from model to model, but here are some common metals and their applications. Before purchasing, consider a unit constructed of materials that can withstand the demands of your commercial kitchen.

Aluminum is the most lightweight and inexpensive metal used to build reach-in refrigerator equipment. Manufacturers routinely build the back, side, and top panels of their cabinets out of aluminum. Because it's a softer metal, aluminum is more prone to denting and scratching than other materials, but that generally isn't a problem because aluminum surfaces aren't exposed to passing traffic. One major advantage to aluminum is that it doesn't rust like steel and iron, no matter how badly it's abused.

Aluminum can be finished to match stainless steel closely, providing a cohesive look while enabling the commercial reach-in refrigerator to be sold at a competitive price. Reach-in refrigerator interiors also are frequently constructed of aluminum. Manufacturers employ a few methods to enhance the durability of aluminum interiors. Some apply a clear coating to the material while others paint it white. Each of those coatings make the aluminum easier to clean and more resistant to scratching.

Galvanized steel is an affordable steel, coated in zinc to give it rust-resistant properties. Galvanized steel is the least attractive of the three main metals. It has a dull, blotchy finish that makes it a poor choice for building exterior components that'll be exposed. However, galvanized steel is a durable, economical choice for components such as reach-in refrigerator tops, bottoms, and backs. It enables manufacturers to keep costs low without sacrificing durability.

Stainless steel is the most durable material used in the manufacture of commercial reach-in refrigerators. Stainless is strong and resists scratching, denting, and bending. It's also highly resistant to rust, which is important in reach-in refrigerators because they're often exposed to moisture and acidic products. Most standard-duty reach-in refrigerators will be built with stainless steel fronts and interior floors, the two surfaces that see the most abuse from life in the kitchen. Heavy-duty, commercial reach-in refrigerators are mostly or entirely built of stainless steel. Such a reach-in refrigerator configuration is often specified for institutional settings, especially high-volume kitchens.