Diagnose Walk-in Cooler & Freezer Refrigeration Problems

A systematic approach to walk-in cooler and freezer maintenance is the technician’s best guide.

The ubiquitous walk-in cooler or freezer is an essential part of many cafeterias, restaurants and convenience stores. It is also a large energy user in these facilities but is rarely considered until problems emerge.

Problems include failure to maintain pressure and compressor failure, both of which can result in expensive losses to the products stored in the cooler. These problems, as well as unnecessarily high energy use, can be avoided by observing equipment and taking corrective action.

Evaporators
Moisture from the air freezes onto the evaporator coils (the cooling coils in the freezer) and forms an insulating barrier to heat transfer. Airflow also decreases as the passages narrow due to ice buildup. Each evaporator has a defrost cycle to melt frost/ice that has built up on the evaporator coils. Water from the melted ice is drained from the freezer . . . ideally.

11 Tips for Purchasing a Walk-in Cooler or Freezer

It’s important to carefully select your walk-in because it’s a major purchase that will have a lasting effect on the operation of your business. Before diving headlong into this purchase, here are a few items to consider before making this decision.

  1. Storage Space – If you’re running a restaurant, you will need approximately 1.5 cubic feet of storage space for every meal you serve per day. Read this article for a more in-depth sizing formula. It’s better to have too much storage space than not enough. However, your walk-in shouldn’t be exorbitantly large because your monthly operating cost generally increases as its size increases.
  2. Location of Box – Whether you’re going to locate your walk-in indoors or outdoors, make sure you have adequate space to accommodate the box. Outdoor walk-ins will require a rainroof, refrigeration hood and a drip cap for over the door (if the door doesn’t open from within the building). Assess the floor to make sure it’s suitable for load-bearing. If you have a concrete floor, a walk-in cooler can be placed on it. If the walk-in is going on a wood frame floor, it will require floor panels. A walk-in freezer always requires an insulated floor.
  3. walkin remote refrigeration
    A walk-in with remote refrigeration.

    Refrigeration System – Confirm that you are getting a refrigeration system that is sized correctly for your walk-in. If your system is underpowered it will run often and wear out quickly. If your system is overpowered it will not cycle enough to effectively remove humidity from the box and may cause icing. There are different types of refrigeration systems with different purposes and benefits. For example, remote refrigeration can be located outdoors when your walk-in is located indoors. This is beneficial because you’re not adding heat or noise to the room where the walk-in operates. It’s also important to know the voltage requirements for your building (single or 3 phase power). In general, commercial buildings will use 3 phase power and residential will use single phase. Learn more about the different types of refrigeration for walk-ins.

The Brew Cave on NBC’s Take It All

U.S. Cooler’s Brew Cave had the wonderful privilege to be featured as a prize on a number of high profile game shows in December, one of them being “Take It All”.

On December 10th, the Brew Cave was a round 1 prize on the premiere of NBC’s week-long event Take It All. Take It All, hosted by Howie Mandel, is a “Yankee swap” style game show in which contestants can take an opponent’s prize or get an unknown prize from the “dream screen”.brew cave take it all

The Brew Cave is a walk-in kegerator for the consumer market that features a LED lit glass door, 4” thick insulation, an external tap and storage space for over 30 cases of beer and 6 kegs. Follow Brew Cave on Facebook or Twitter.

Replacing Your Hinges and Latches

When replacing hinges and latches for walk-in refrigerators it is important to get an exact or comparable replacement part. The back of the part will stamped with a series of numbers and letters called a mold number. The back may also read “flush” or have the offset size (e.g. 1-3/4″). It is important to have that number on the back to ensure you get the proper replacement. Additionally, having the serial number of your walk-in (often located in the door jamb on the hinge side or in a corner inside panel) can be a huge help if you’re ordering the replacement part from the walk-in manufacturer or your parts supplier.

hinge with serial number
Call the walk-in manufacturer or get the mold number off the back of the part.

Hinges

Walk-in cooler and freezer hinges are either flush or offset. The easiest way to determine which style you have is to place your hand on the outside wall of the walk-in and slide it towards the door. If the door stops your hand from moving across the door, then you have an offset door. If your hand slides across the door, it is flush.

Determine the offset measurement by measuring from the wall surface to the door surface. The offset measurement combined with the mold number on the back will ensure you receive the correct hinge.door offset

Reduce Energy Costs in Your Walk-in

Whether you own a restaurant, bar or convenience store, your walk-in cooler or freezer is likely one of the largest line items in your energy usage. If you’re looking to reduce your overhead it is imperative you do all you can to optimize your walk-in for maximum energy efficiency. In this article we’ll cover everything from maintaining your refrigeration system to energy saving accessories.

Maintain your Walk-in

door with icing
Investigate icing around your door immediately

Check your door sweep, door and panel gaskets for any rips, cracks or icing and replace if necessary.  Icing around the door could indicate a failure of the gasket, heater wire, or the door closer. Lubricate hinges twice a year to keep them closing smoothly. Make sure your walk-in is organized and covered items are clearly labeled to reduce the amount of time spent searching for ingredients.

Maintain your Refrigeration

Every six months, visually inspect your unit for corrosion, electrical issues, leaks or improper fan operation. Clean the evaporator coil and blades. Make sure the drainage system is clear of any debris. Ensure airflow to the unit is unobstructed.

There are many more steps to take to make sure your refrigeration unit is running efficiently. Visit this page for more refrigeration maintenance tips.

Upgrade Your Refrigeration System

New Department of Energy standards went into effect in 2009. If your walk-in was manufactured before 2009, your refrigeration unit is likely less efficient than newer energy act compliant units.

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.