Operators can load pass-through refrigeration from either the front or back. Common applications for this type of upright, reach-in refrigeration include schools, universities and hospitals because these units provide self-service from the front. This provides the means for easily restocking chilled product without interrupting service.

Pass-through refrigeration is categorized by size, with one-, two- or three-section models available for different applications.

Depending on the operation and use, operators can choose from a variety of door configurations. These include full-height solid doors, which are standard, or optional full or half glass doors or half-height stainless doors. A single section unit will have two half doors on each side, while a two-section type has two half doors on each side. A single-section model has six half doors on each side. Pass-throughs also can have a combination of glass and solid doors on either side.

In applications like a servery or scatter system, namely operations that display food for self service, pass-throughs with glass doors on the customer side and solid doors on the kitchen side tend to be popular choices. This provides better merchandising and visibility for products within the refrigerator. For buffet use, it may be the opposite with solid doors facing the customers and glass doors facing the kitchen so staff can see when replenishing becomes necessary.

Standard sizes range from 27 to 30 inches wide. Some types are narrower left to right, measuring 24 to 25 inches. Models also are available with shallower depths that are 36 inches front to back for operations where space is at a premium.

These units generally feature 2-inch foamed-in-place polyurethane walls with stainless steel construction. Some units come with recessed fans in the top of the pass-through cabinets to provide additional space inside the cabinet.

Aspects to consider when purchasing a pass-through refrigeration cabinet include the available space for the unit, the specific application, and the volume of product being passed through the equipment. It is also important to consider interior cabinet visibility and whether the contents need to be visible. If so, glass doors should be considered.

Depending on the model and manufacturer, standard features may include top-mounted compressors, electronic controls, digital readouts, automatic defrost, self-adjusting magnetic door gaskets, 4-inch casters, LED lighting, field reversible solid doors, centered key locks, stainless steel finishes or stainless exteriors with anodized aluminum interiors, and heavy-duty epoxy-coated shelving.

Operators can choose from a number of options, such as extra epoxy-coated shelves, extra stainless steel shelves, full door pan slides, half door pan slides, full glass doors, half glass doors, half solid doors, and legs in lieu of casters. Remote refrigeration represents another option when space is at a premium. Data loggers, popular in hotel and health care facilities, log refrigeration temperatures and keep track of how often the unit goes into defrost mode.

Prison packs are available for added security, which include locks and heavy-duty casters. The refrigerators also have various mounting capabilities. For example, this equipment can be permanently installed in a wall opening and mounted on 6-inch legs or can have a base that is sealed to the floor, which prevents food from getting underneath. Units that are in serving lines or buffets are typically on casters for easier mobility.

The newer pass-through units feature standard energy-efficient LED lighting that lasts up to 50,000 hours, reduces electrical usage and produces minimal heat, resulting in lower utility costs.

The U.S. Department of energy updated its refrigeration efficiency standards to replace the 2009 version. Depending on the case type, some models must meet energy reductions greater than 70 percent. These requirements go into effect on March 27, 2017.

In addition, the Environmental Protection Agency has published a Final Rule which delists common hydrofluorocarbons (HFC) utilized in the commercial refrigeration industry. Examples include R-134a, R-404A and R-507A. Refrigerants that are permitted include naturals R-290 (propane) and R-744 (carbon dioxide) as well as newly listed Significant New Alternatives Policy (SNAP) refrigerants R-450A, R-448A, R-449A and R-513A. For remote cases, existing refrigerants R-407A, R-407C and R-407F will still be allowed.