Walk In Freezers

The biggest difference between walk-in coolers and walk in freezers is the thickness of the insulation. Walk-in coolers typically use 4” insulation, whereas the insulation in walk in freezers is usually 5”- 6” thick. This extra thickness supports the lower temperatures — which sometimes go down to -50∞F — that walk in freezers need to maintain.

A walk in freezer removes heat from its insulated compartment, making it colder.

Here’s how it works:

• On the outside of the walk in freezer, a compressor takes low-temperature, low-pressure refrigerant gas and squeezes it. As the pressure increases, so does its temperature.
• When the temperature is higher than that of the outside air, heat passes from the hotter refrigerant to the cooler outside air.
• The refrigerant then passes through an expansion device. As the refrigerant’s pressure drops and it changes state into a liquid, its temperature also drops until it’s colder than the air in the insulated space.
• As the cold refrigerant passes though the insulated space, heat from the surrounding air transfers to the liquid.
• The refrigerant then passes outside of the insulated space, where it enters the compressor and begins the cycle again.

Most walk in freezers are set between 0∞F and -10∞F. Some applications, such as pharmaceutical, require temperatures as low as -50∞F.

The thicker insulation of walk in freezers is certainly capable of holding temperatures required for refrigeration, but you would need to replace the refrigeration system with one designed to hold temperatures at 35∞F or use a dual-temperature unit.

Although it can’t hurt to keep sensitive items away from the door and closer to the floor than the ceiling, keeping frozen items cold helps them resist slight changes in temperature from rushes of warm air or “hot spots”. To that end, it’s important to only put items in your walk in freezer that are within 10∞F of the desired temperature.
If you need to bring large amounts of food or product to freezing temperatures, we can advise you on the best Polar King size and type of system for your application.

According to OSHA 1910.36(d)(1), “Employees must be able to open an exit route door from the inside at all times without keys, tools, or special knowledge.”

At Polar King, our walk in freezer doors are easy to open from the inside, but we recommend installing an alarm as a failsafe to give employees the confidence they need to do their jobs effectively.