Walk-in Refrigeration

Walk-in refrigerators and freezers, which chill and hold food items at desired temperatures, are integral parts of many foodservice operations.

Generally speaking, a walk-in cooler maintains an internal temperature of 38 degrees F or warmer, while a freezer maintains a temperature of less than 32 degrees F. With proper care, these units can last decades.


With good maintenance, the panels that comprise a walk-in's walls can last for many years. The parts that need the most care and replacing include the doors, gaskets and mechanical refrigeration components. It is important to perform proper maintenance not only to ensure the operation gets the most from these parts but also to guarantee that the unit functions at a highly efficient level. With the right care, these components can last 10 to 20 years, depending on the nature of the foodservice environment.

Doors will show their wear first, specifically with the hinges, frames and seams. That's because a significant amount of traffic will enter and exit a door during peak periods such as preparation and serving. Often, during these busy periods or when taking in deliveries, employees will use a variety of items to prop open unit doors. This practice puts unnecessary strain on the hinges and frames, significantly shortening their lifespans.

Signs that a walk-in's door or frame may need replacing include sagging or moisture around the opening. Of course, moisture on the outside can also be a sign that a gasket needs to be replaced.

Here are a few key questions to ask when it comes time to purchase a new walk-in refrigerator or freezer:

Is it necessary to buy a custom-built walk-in, or are there other options?
Depending on their budgets, foodservice operators can choose from several types of walk-in units. Custom-designed walk-ins can be configured in practically any size or shape to suit an operator's needs but may cost more due to design time.

Quick-ship walk-ins come in preconfigured sizes that are available for delivery in relatively short order. A stock model generally comes with either a remote refrigeration system or with a packaged system containing the condensing unit and evaporator coil in one housing.

Factory preassembled walk-ins ship from the manufacturer ready to set in place. All the operator has to do is provide electricity at the job site.

What are the benefits of buying a combination walk-in cooler and freezer?
Depending on the particular operation, this can be a very efficient approach because the two units will share a common wall, thus reducing the need for panels. This approach can also improve space allotment in the kitchen.

How do we decide what size unit to purchase?
To determine how large a unit is necessary, an operator should consider the following questions: How much product will be stored in the unit? Will product come into the unit already cold, or will it be warm and require chilling?

Properly sized and designed walk-in units can help with food safety. Simply designating separate sections of a walk-in cooler for raw and ready-to-eat products will minimize the chances of cross-contamination. At least one accurate thermometer should be placed in the warmest part of the walk-in cooler to measure the air temperature, and shelves should be at least 6 inches off the floor for ease of cleaning.

Should we place the walk-in outside or inside the facility?
The available space at the foodservice operation will answer this question. Provided the necessary space exists within the facility, walk-ins are easily expandable. Operators may simply add on however many panels are needed to generate the desired box size.

Are there any special considerations for outside units?
An outdoor unit needs to be placed on a prepared slab and should be properly aligned with the main building to allow easy access for staff. In some instances, you may want to fasten the unit to the building. An outdoor unit also requires a membrane roof. And it may be advisable to have a pitch on the roof to allow rainwater, or even snow in colder climates, to run off. In the case of an outdoor unit in a climate that gets lots of snow, it may be advisable to insert a post and beam for additional roof support. And in locations prone to hurricanes, such as the southeastern United States, it is advisable to fasten units to the ground.

Does a walk-in unit need a special floor?
The floor is one of the most critical components of any walk-in unit. And exactly what type of floor is necessary depends on a number of critical factors, such as whether it is a cooler or freezer, the location of the unit and how food will enter and exit the space.

For example, wheeled traffic such as pallet jacks or heavy carts can overload a walk-in's floor. In those instances, it is imperative to have a durable structural floor with internal support. If staff mostly carry items in by hand or even transport goods using two-wheel hand trucks with inflated tires, the unit does not require a floor that's quite as heavy-duty.

In most cases, walk-in freezers must have an insulated floor of some kind. The exception to this rule is when a walk-in freezer is placed on an insulated slab at grade level. Conversely, walk-in refrigerators at grade level that maintain an internal temperature of 38 degrees F do not necessarily require an insulated floor.

Anytime a walk-in cooler or freezer is on a second floor or higher, an insulated floor is required. And if a unit has a raised floor, installing a ramp may be necessary to facilitate loading and unloading of product.

NSF requires the interior floor of a walk-in to lock into the panels. A gasket must be placed along the area where the floor and panel intersect.

Where should we place the condenser?
To save space and keep noise levels to a minimum, consider placing the condenser outside of the building and run a line to the box, when possible. This configuration requires the operator to have the right ambient controls for the environment in which the condenser will reside. It's important to keep the condenser at the manufacturer's suggested temperature and clean and free of debris. In addition, hard copper pipe should connect the condenser and cooling unit, provided the box uses uncharged lines.

Speaking of the cooling unit, where should we place that?
Standard placement of the cooling unit is roughly 12 inches off the back wall. This allows for proper air intake and circulation. Some makers offer center ceiling mounts for their units but also require proper clearance above the box. Work with the supplier to determine when this type of cooling unit is appropriate.

What are the most common mistakes operators make when purchasing walk-in refrigeration units?
One common mistake is failing to plan for the future development of the foodservice operation and how that will impact the use of the walk-in unit. For example, will space requirements increase soon, or will it be necessary to move the walk-in someday? If so, cam-locking panels are a benefit because they make it easier to expand or dismantle the walk-in and move the unit when necessary.

Other common mistakes include not sealing the unit properly, which allows for air transfer, and not having a level and smooth base on which to place the unit.

It is also important to understand what the warranty covers and know whom the local service agent is.