When to Replace an Old Walk-in Cooler or Freezer

leaking water
Freezer panels will sometimes leak water when returned to room temperature.

Buying a new walk-in cooler or freezer can be a large expense, but so can inflated electricity bills. Depending on how bad of shape your current walk-in is in, a new walk-in could pay for itself within a year or two.

How long is the lifespan of a walk-in?

There’s no set time limit for when you will need to replace a walk-in. This depends on many factors including the original quality of the refrigerator, type of insulation used, how well the box and refrigeration were maintained, and if it has suffered any harsh usage. After 10 years or when your warranty runs out, you should do a cost-benefit analysis for purchasing a new walk-in.

ice accumulation
Ice accumulation on panels should not be ignored.

What are some signs that I need a new walk-in?

  • If you notice a steady increase of energy bills from month to month, it could be an indication of the gradual decline in the R-value of your insulation.
  • If there is condensation or ice buildup on your walls or ceiling it could be an indication that your insulation has failed and is saturated with water or ice. This moisture accumulation could also be the result of air leaks between panels or elsewhere.

Walk-In Cooler & Freezer Installation Tips

All U.S. Cooler walk-ins are test assembled in our plant prior to shipment. This ensures problem free on-site installation. If you have had problems setting up your walk-ins, we have some tips that may be helpful.

1. Receiving your walk-in: When your walk-in cooler or freezer is delivered by the freight company, it is critically important that you inventory the items delivered.

packaged for shipping
Most walk-ins are shipped “knocked down” or in stacks of panels.

a. You must be sure when you sign the delivery receipt, you have received the freight in good condition and not damaged in anyway. The person signing the delivery receipt is responsible for inspecting the freight.
b. If you see any damage to the container or boxes, this is a good sign that you may have hidden damage. If you have a camera, take pictures of any damage to your freight, even before it is taken off the truck. Call U.S. Cooler and ask for Customer Service if you see a problem with your shipment. When you call, have your order number available. The order number allows us to pull up all details needed to answer your questions.
c. Insist that the driver does not leave until your satisfied all freight damage has been noted on the delivery receipt before the driver signs the delivery receipt.

2. Take time to read the instruction manual and review drawing: Before you get started take out the installation instructions and drawing package. Inventory your parts against the drawing to be sure you understand the layout. If you have any questions on how to assemble the walk-in call U.S. Cooler or the manufacturer of your walk-in and ask for Customer Service.

3. Make sure your area where the walk-in will be installed is flat: Level is critical when installing a walk-in cooler or freezer. Before installation you should get an exact tolerance of the entire space you are planning to install the walk-in. The longer the box, the more important it is to have a level area. Floorless boxes should be shimmed inside the vinyl screed to prevent gaps and air infiltration. A liquid leveling compound is very useful for floors that are not completely level.

standard size walk-in

Operating Costs for Walk-In Coolers and Freezers

Before purchasing your walk-in, you may be wondering how much it will cost to operate your walk-in.

Estimates for Standard Sized Walk-ins

To give you a rough estimate of how much it cost to operate a walk-in cooler or freezer, using the national average of $0.1071 per kilowatt, look at the chart below.

Cooler Average Cost per month Freezer Average Cost per month
6×6 $70.74 6×6 $244.13
6×8 $70.74 6×8 $244.13
8×8 $126.49 8×8 $244.13
8×10 $119.30 8×10 $372.27
8×12 $119.30 8×12 $372.27
10×10 $151.07 10×10 $372.27
10×12 $151.07 10×12 $435.66
Note: The above figures are estimates in a controlled environment; your exact numbers will vary.

*These numbers were figured using the 12-month rolling average of $0.1071 kilowatt hour cost. According to the Energy Information Administration this is the average cost in the United States for commercial electricity as of November 2014.

This chart was created using several assumptions that can affect your actual operating cost.

  1. The type of insulation in the walk-in.
  2. Efficiency of the refrigeration system.
  3. Inside and outside temperature of walk-in.
  4. Where the walk-in is located.
  5. The temperature and the weight of the product entering the walk-in.
  6. How often the door is opened.
  7. The age of the walk-in.
  8. Cost of electricity.

This is just to name a few. If you would like to be more accurate using your electric rate, follow the instructions below.

Troubleshooting Defrost Problems

When troubleshooting walk-in freezers, technicians often find a frozen evaporator coil. Although there are several possible causes, one common cause involves the defrost system. For some reason, the system is not properly defrosting the evaporator’s coil on a regular basis. In order to effectively troubleshoot this problem, a technician must understand the design and operation of the defrost systems typically used.

frozen evaporator coil
A frozen evaporator coil from improper defrosting.

One popular method of defrosting walk-in freezers is the electric defrost system. This is comprised of several components, including a defrost timer, resistive heater(s), defrost termination switch, fan cycling control, and drain line heater. An electric resistance heater is placed on the outer surface of the evaporator’s coils. The energized heater supplies enough heat to completely defrost the coils.

The resistive heaters used on a typical electric defrost system are sized to provide sufficient heat to effectively defrost the coil’s surface. Their capacity is normally rated in watts per foot. They are shaped to fit snugly onto the coil surface, creating efficient heat transfer during defrosts.

Most heaters are manufactured for a specific coil, and when replacing these heaters it is best to obtain the OEM replacement. Universal defrost heaters are available, but matching their wattage and shape may be difficult.

A defrost timer controls the entire defrost operation. It initiates the defrost cycle, controls the operation of the compressor and defrost heaters, and is part of the defrost termination. Defrost timers can be adjusted to initiate defrost from just once a day to several times a day.

The actual number of defrosts per day depends upon the location of the walk-in. Walk-in freezers are usually designed to defrost once or twice a day. The more humid and warm a location, the more defrosts will be needed. If a system needs to be defrosted more frequently, add only one additional defrost period at a time and monitor the results. Adding too many defrost periods will not be beneficial to the system or the customer.

In a common wiring diagram for a time-initiated, temperature-terminated electric defrost system the time motor (TM) is energized continuously. Normally closed contacts 2-4 of the defrost timer are wired in series with the compressor and the evaporator fan motor (EFM). Normally open contacts 1-3 are wired in series with the electric defrost heaters and the timer release solenoid (TRS).

The timer motor controls the operation of contacts 2-4 and 1-3. They work opposite each other. When contacts 2-4 are closed, 1-3 are opened. When contacts 2-4 are opened, 1-3 are closed. When the timer motor initiates a defrost, contacts 2-4 will open and 1-3 will close. This stops the compressor and the evaporator fan motor, and energizes the defrost heaters.

EC Motor Start-up Issue

Electronically Commutated Motor AO SmitAs of January 1, 2009, all walk-in manufacturing companies must sell their refrigeration units with Electronically Commutated (EC) motors. EC motors lower energy costs and significantly improve the walk-in cooler or freezer performance. These energy efficient motors are offered as a complete unit or as a drop-in replacement. Whichever your use is, if you are not familiar with the EC motor it may seem odd when you initially start it up.
When starting an EC motor, the motor must know where the rotor is located in order to start and continue to run. When power is first applied to the motor, the controller will apply a gradually increasing amount of current to all three windings in the motor over a period of 2 seconds. This will cause the rotor to move to a known location. This move will range from no movement at all if the rotor has stopped in the location needed for the next start or may be a much larger movement if it was a longer distance  from where it needed to be. With a fan blade attached, it may even overshoot and move backwards to get to the right location. After that 2 second “positioning” period the controller will start applying power to different phases in a slow rotating pattern that increases in speed over the next 2 seconds until the rotor is moving fast enough for the controller to be able to detect its location. This second phase of the start cycle usually happens so quickly that you cannot really see what is happening. Within 3 to 5 seconds of applying power, the motor should appear to be running normally, but during those first 2 seconds the movements may seem as though the unit is having troubles starting or is broken.

Cutting Down On Cooler Costs

Whether your chain is gearing up for LEED certification or just hoping to save on the electric bill, instituting an energy management solution can pinpoint energy waste.

leed certification sealEnergy reduction remains an ongoing quest for convenience store operators as they look for ways to cut costs in an effort to improve their bottom lines.

Building stores to LEED (Leadership in Energy and Environmental Design) standards and seeking LEED certification is something more chains are pursuing, including Kum & Go, Kwik Trip and Quick Chek, which just opened its first LEED-certified store last month in Bayonne, N.J.

LEED is an internationally operated program encompassing the design, construction and operation of high performance green buildings established by the U.S. Green Building Council and verified by the Green Building Certification Institute (GBCI). It provides third-party verification that a building was designed and built by implementing strategies aimed at improving performance in areas such as: energy savings, water efficiency, CO2 emissions reduction, improved indoor environmental quality and stewardship of resources and sensitivity to their impacts.

Beer Caves – The Perfect Beverage Refrigerator

beer cave in convenience storeRegardless if you are remodeling or building new stores, why not increase the use of your space and install a beer cave for your alcoholic beverages? Beer caves have grown to be very popular in the convenience store industry offering a bright inviting room for customers to browse their selection. Beer caves can come in any shape or size. They are all custom designed to fit your plans. Consider the advantages the beer cave can provide for you and your customers.

inside a beercave
Beer Caves allow you to have much more merchandise readily available to consumers.

Bright lights, glass doors and windows can make an old drab corner turn into an inviting alcoholic beverage oasis. It is proven that bright lights and colorful graphics grab people’s attention attracting more customers to the product. Customers like to see all their choices right in front of them. The beer cave consolidates all beer and alcoholic beverages in one area so it is easy for people to find what they are looking for, grab and go.

New Refrigeration on Used Walk-ins – Is it EISA compliant?

The Department of Energy (DOE) has written their interpretation on compliant refrigeration vs. non-compliant refrigeration on walk-in coolers and freezers. Below, DOE explains that any component added to a previously installed walk-in cooler or freezer and manufactured after January 1, 2009, must meet EISA guidelines. This is a draft document and comments and suggestions must be submitted to the Department of Energy prior to February 20, 2012.

The Interpretation from the Department of Energy (DOE)

This is a draft document and does not represent a definitive view of the agency on the questions addressed.

This and other guidance documents are accessible on the U.S. Department of Energy, Energy Efficiency & Renewable Energy web site at: http://www1.eere.energy.gov/guidance/default.aspx?pid=2&spid=1.

Guidance Type: Conservation Standards, Enforcement
Category: Commercial Equipment
Product: Walk-in Cooler and Walk-in Freezers
Guidance Version: DRAFT
Issued: January 20, 2012
Comment Period Closes: February 20, 2012

Q: What are the relevant dates for compliance with the prescriptive requirements for walk-in coolers and walk-in freezers? For example: If a newly manufactured component of a walk-in cooler or walk-in freezer is installed in a walk-in box manufactured prior to January 1, 2009, does it have to comply with the prescriptive requirements of 10 C.F.R. § 431.306?

A: The following is a draft U.S. Department of Energy (DOE) guidance document regarding commercial walk-in coolers and walk-in freezers. This draft guidance document represents the Department’s interpretation of its existing regulations and is exempt from the notice and comment requirements of the Administrative Procedure Act. See 5 U.S.C. § 553(b)(A). Therefore, the Department is accepting comments and suggestions from the public until February 20, 2012. Comments and suggestions should be provided in WordPerfect, Microsoft Word, PDF, or text file format by sending an email to WICFEISA2007Guidance-2012-0001{at}ee.doe.gov. Please also include the docket number EERE-2012-BT-STD0001.

At the end of the comment period, this draft guidance document may be adopted, revised or withdrawn.