Walk-in Cooler & Freezer Shopping Tips

shopping walkin coolerBe aware when shopping for walk-ins online that you are comparing the same size box and refrigeration. Some companies are offering smaller sized refrigeration packages, which make it look cheaper upfront but may not provide you the results you are looking for.

Some systems, whether they are coolers or freezers, are designed only to hold the temperature of the product coming in and are not designed to pull-down the temperature of the product to the desired holding temperature. Pull-down happens when there is product entering the cooler or freezer that is warmer than the desired temperature and needs to cool in a short amount of time. For example, when a restaurant owner has a large pot of soup that needs to be cooled quickly to avoid bacteria growth, the refrigeration must be able to cool the soup to the desired temperature in a reasonable and safe time while maintaining the holding temperature in the cooler/freezer. Systems designed for holding only and not to pull down the temperature of the product coming in will only work properly if products entering the box are already at the desired temperature, either cold or already frozen.

The industry standard design temperature for freezers is at -10° F. Some online companies are selling their freezer refrigeration at a holding temperature of 0° F. If you try to run a walk-in designed for 0° F holding temperature and set the thermostat to -10° F, it will run constantly trying to meet the -10° F temperature it was not designed to hold. This will shorten the life of the compressor and may cause the coil to freeze and consequently warm up the box to melting temperature, damaging the food stored inside.

Before purchasing, you must understand the difference and what implications it could have on your business. Most perishable items that are stored in a freezer are not frozen to start with and will need to freeze and stay frozen for a period of time. If the box is designed for holding temperature only and is set at 0° F, the refrigeration will work harder and longer to pull the temperature inside the box back down to 0° F once warm food is stored in the freezer. Frozen products, such as ice cream, hold up better at -10° F rather than 0° F. When a freezer goes into defrost it can raise the box temperature by 10-15°. If your box is set at 0° F, a 10-15° temperature swing can cause some products to be damaged or melted. When dealing with food it is imperative to make sure the holding temperature in the freezer is low enough to keep products frozen, protecting from bacteria or other hazards that spread through food not refrigerated correctly. (Check with your local health codes for the required holding temperature of your walk-in cooler and freezer.) It is also important to note that when refrigeration is working longer and harder, your energy costs will increase as well as the chances of your refrigeration breaking down or having inefficiencies.

Every state has requirements for storing cold food; here is an example of Illinois’s Administrative Code.

Defrost termination fan delay control

The defrost termination/fan delay control is a temperature-activated, single pole-double throw switch controlled with a remote sensing bulb (Fig. 1). The control can be an adjustable type. One example of the installation of an adjustable defrost termination/fan delay control is on a walk-in freezer’s evaporator (Fig. 2).

fig. 1
fig. 1

The control is wired into the refrigeration circuit. The control’s remote sensing bulb is located high on the evaporator where the frost is likely to clear last. The function of this temperature-activated switch is to terminate defrost when the evaporator coil has been defrosted, and to delay the evaporator fans from coming on immediately after defrost.

fig. 2
fig. 2

Defrost time clocks can be programmed for certain defrost duration periods. This is a time duration set at the time clock in minute increments. For example, a defrost time clock on a freezer could be programmed to defrost every six hours (four times daily), and have defrost durations of 40 minutes. However, there will be times throughout the year where the coil does not need the entire 40 minutes. These times could be from low usage of the freezer where the door openings are minimal, or when the humidity is low and not much frost accumulates on the coil. This is where the defrost termination part of the control comes into play.

Read the full article to learn how the defrost termination & fan delay systems work

Smart Defrost Kit for Walk-in Refrigeration

Make your refrigeration smart and save money by adding a Smart Defrost Kit (SDK) to your walk-in refrigeration system. SDK decreases the amount of defrost cycles in commercial walk-in refrigeration units by 30-40%. Typical electrical defrost refrigeration systems are scheduled to defrost at regular intervals, which is not always the most efficient or safe way. For applications where food safety is critical such as restaurants, convenience stores and grocery stores, the SDK works to protect perishable products as well as enables refrigeration systems to operate more efficiently, ultimately saving you money. All systems are different, which is why SDK takes time to study your system and helps decrease energy costs by keeping the box temperatures consistent. The SDK works by using temperature and pressure sensors to constantly monitor the system.

sdk-kitClick here for more information on Smart Defrost Kits.

Check out their savings calculator that demonstrates how much money you could save by installing a Smart Defrost Kit.

Meeting 2009 EISA Walk-in Cooler & Freezer Standards

The federal government’s EISA (Energy Independence & Security Act) standards went into effect Jan. 1st, 2009. This act was intended to improve energy efficiency within the refrigeration industry as well as many other industries. AHRI reports there have been some concerns since there are no enforcement mechanism or standard testing methods built into the act; non-compliant walk-in manufacturers will stand to benefit. These manufacturers will be able to beat compliant competitors on price (due to the lower input costs of their non-regulation walk-ins). Be sure that when buying a walk-in, you check to make sure they are EISA compliant.

The AHRI (Air-Conditioning, Heating, and Refrigeration Institute) is trying to raise awareness about what this act mandates among distributors, installers, and consumers. They have created a checklist of the standards walk-in coolers & freezers are required to meet that can be found at ACHR The News. Use this checklist to ensure the walk-in unit you are about to purchase meets the EISA standards.