When making a decision on which walk in cooler or freezer to buy there are many things that must be considered. In the following we hope to go through all these considerations and provide you with the information you need to make an informed decision.

WHAT IS IMPORTANT TO YOU:

Most walk in coolers and freezers manufactured today are constructed of foam insulation bonded between two sheets of sheet metal and come equipped with cam locking devices to allow the assembly of the panelized walk in on site.

There are a few companies that also provide a completely assembled unit that is delivered on a truck and dropped off at your location. These are usually for outside the building installations. Refrigeration systems are also usually provided in several types of configurations along with the walk-ins. These systems will be explained later.

All walk-ins coolers and freezers are designed to keep the products inside cold.

When considering the purchase of a walk in you must consider what is important to you. If a low up front price is most important due to budgetary consideration, then the up front price may be a very important consideration in buying your walk-in. (Usually lower costing walk-ins have a lower up front cost but when considering the higher energy expenses they may cost more over the life of the unit). If overall cost of the walk in over the life of the unit is important then a little higher up front cost but lower energy use and maintenance cost over the life of the unit may be the way to go. Either way you go, quality workmanship and materials are a must when buying a walk in.

Make you decision on your needs and not what someone is trying to sell you. After all customers needs are not the same, one product does not fit all.

MATERIALS:

INSULATION MATERIALS:

There are three types of insulation used in walk-ins today; expanded polystyrene insulation, polyurethane insulation and extruded polystyrene insulation. Each insulation is constructed of gas filled cellular plastic foam and each brings with it different benefits to the customer.

1. Expanded Polystyrene - This insulation is the same type of insulation used in Styrofoam cups. It has been a reliable insulation material that has a lower up front cost but also has a lower initial 90 day aged R-value (The higher the R-value the more resistance to heat flow thus less energy used) than the other two insulating foams. Its R-value is 4.75 per inch or R-19 for a four-inch panel. It has a moderate resistance to moisture penetration, which lowers the insulation’s R-value and has moderate ability to keep its R-value throughout the years. It has been very successfully used in the manufacturer of quality walk in coolers and, in higher densities and thickness freezers.

2. Polyurethane - Polyurethane is among many other things used as packaging foam and in the construction of walk through outside residential and commercial doors. It has a high 90 day aged R-value of R-24 but is less capable of moisture resistance and R-value retention. It can loose as much as 75% of its R-value to as low as (R-6) over the life of the product. It is a good insulation for manufacturing products that include intricate parts that need to be bonded together. It has been used a long time in the manufacture of walk-in coolers and freezers.

3. Extruded Polystyrene - This insulation is used in insulating underground concrete foundations and floors. It has a high 90 day aged R-value (R-20) and has a great moisture resistance and ability to retain around 75% of its R-value or (r-15) over the life of the product. It has great structural strength of up to 4 times that of polyurethane and expanded polystyrene. It is a little higher than expanded polystyrene insulation but about the same as polyurethane insulation. It is better than expanded polystyrene and polyurethane insulation if overall performance is considered. It is an insulation that will continue to pay dividends in energy savings for as long as you own the walk-in.

METAL SKINS:

Walk-ins come with several different types of skins depending on what the customer desires. Each of these skins provides different benefits to the customer.

1. G 90 Galvanized - This economical material is probably the most popular skin used in walk-in coolers and freezers. The G90 depicts the type of galvanizing with G60 having less resistance to corrosion than G90. G90 is the minimum needed in producing a walk-in cooler or freezer. Its advantages are that it is reasonably priced, strong and more dent resistant. Its disadvantage is that it can develop what they call white rust if it is not handled correctly in installation and if caustic cleaners are used. Once white rust has formed it can turn into red rust if not treated. G90 can be stucco embossed making it even stronger and also give it the aluminum embossed look that is sometimes desired in the market. G90 is usually provided in 26-gauge minimum in thickness for walls and ceilings and a 16-20 gauge thickness for floors. Note that G90 galvanized floors are not approved for manufacture by the National Sanitation Foundation for food service applications. Galvanized floors however can be used if quarry tile is installed over the floor before use.

2. Aluminum - Aluminum as a raw material is more sensitive to price fluctuations. It is very resistant to corrosion except for salt spray and is not as strong as other metals and can dent very easily. Aluminum is usually provided in 40-60 mill thickness for walls and ceilings and 100-120 mill thickness for floors. Sometimes aluminum floors are 1/8th-inch thick and diamond tread-plate embossed to add further strength. Most of the time aluminum for walls and ceilings are stucco embossed to increase their strength.

3. Galvalume - Galvalume is steel coated with combination of aluminum and galvanizing material. It has the strength of steel but is twelve times more corrosion resistant than galvanized. It is usually provided in a 26-gauge minimum thickness. It has a gray look that is usually embossed to make it look more appealing. However, is more expensive than both aluminum and G90 galvanized. If up front cost is important this metal may not be desired.

4. Painted G90 Galvanized - Painted galvanized is more expensive than Galvalume but is more resistant to corrosion and has the benefit of providing a choice in color for customers who want the painted look. NSF must approve the paint system used for the walk-in to be NSF approved.

5. Stainless Steel - Stainless steel is the most expensive of all metal skins normally used in walk-in construction. It is the strongest and least corrosive of all the metals and usually comes in 24-gauge thickness. It comes in different polishes such as brushed and polished. Most walk-in coolers come with the brushed look to reduce the visibility of scratches.

Deciding on the skin you desire may once again depend on whether up front or long term savings are important.

REFRIGERATION SYSTEMS:

Refrigeration systems consist of a condensing unit and an evaporation coil. The condensing unit is located outside the walk-in and the evaporator is located inside the walk-in. The compressor compresses gas to a liquid. It is then pumped through the condensing unit coil while a fan blows outside air through the coil. Gas is condensed to a liquid and is then pumped through a small copper pipe into the walk-in to the evaporator coil. There, through the expansion valve located in the evaporator coil the liquid is allowed to expand back into a gas. The expansion of the liquid to a gas causes a rapid chilling of the evaporator coil. Since heat always flows toward cold, inside, the walk-in, air is blown across the evaporation coil to let the coil absorb heat from inside the walk-in. The gas is then allowed to exit the walk-in through a larger copper pipe to the condensing unit where it is once again compressed and cooled to a liquid state and returned to the evaporator coil inside the walk-in. There the cycle is started over.

Refrigeration systems like walk-ins can be purchased with lower up front cost but higher operating cost or higher up front cost but lower operating cost. This decision is up to you and what you deem most important. All of these systems come in different shapes and sizes, which will affect how much you pay up front and how it performs. In the following you will find the different type of systems and their pros and cons.

1. Remote Systems - Remote systems are the least expensive systems to purchase. They consist of a condensing unit, evaporator unit and misc. parts such as expansion valve, site glass, dryer, pump down solenoid thermostat and on freezers a timer and drain heater to install the system. They require the use of licensed refrigeration installer since they are pumped down and charged with refrigerant gas on location. The installer will also charge for any other parts needed for the install such as copper pipe, pipe insulation, connectors and electrical. They are less expensive systems to buy with the walk-in but may cost more over all depending on what the going hourly rate is with the installer and the cost of the parts he provides. They also provide an advantage by allowing the condensing unit to be located outside the building. There the condensing unit can dump its heat without adding extra heat to the building and air conditioning systems.

2. Pre-assembled Remote Systems - Pre-assembled Remote Systems are the same as Remote Systems except all the parts are shipped installed on either the condensing unit or the evaporator coil. Pre-assembled Remote Pre-charged systems come with the condensing unit, the evaporator coil and line set (copper pipes that connect the two units) charged with refrigeration gas. A licensed refrigeration technician will be needed to install the refrigeration system. These systems may or may not be less expensive depending on the cost of the system, the refrigeration service and electronics service charges.

3. Standard Top Mount - Top Mount Systems are self-contained refrigeration systems. They come with all parts, copper lines and refrigeration gases completely installed. A licensed refrigeration technician will be needed to install the refrigeration system. The only downside to these units is that the evaporator hangs down inside the walk-in taking up shelf space and head room in small walk-ins. Some units come with low profile coils that help but do not eliminate this problem.

4. Side Mount Refrigeration System - Side Mount Refrigeration Systems are the same as Top Mount Refrigeration Systems except they are installed on one of the wall panels with bolts that go through the refrigeration plug and wall panel and are attached with nuts on the inside of the walk in. They also require that a condensation drain hose be connected to a drain nearby. A licensed refrigeration technician will be needed to install the refrigeration system. One downside is that you loose shelf space where the evaporation unit extends inside the walk in.

5. Saddle Mount Refrigeration System - Saddle Mount Refrigeration Systems come completely pre-assembled on a bracket that is designed to be mounted over the top of one of the wall panels. These systems must be installed on a panel with slots cut in the top to allow the bracket to go through the wall. These systems are hung over the wall before the installation of the roof. A licensed refrigeration technician will be needed to install the refrigeration system. These units also have the evaporator coil that hangs from the top of the panel but it is more toward the top and doesn’t interfere with the shelving as much as a side-mount unit.

6. Penthouse Refrigeration System - Penthouse Refrigeration Systems are like Standard Top Mount Systems except they do not have an evaporator coil sticking down inside the walk-in. The air inside the walk-in is drawn up through the evaporator coil located with the condensing unit on top of the walk-in to be cooled. A licensed refrigeration technician will be needed to install the refrigeration system. These systems sometimes seem higher in up front cost but when all things are considered including the fact that they are factory assembled and don’t take up space in the walk-in it is less expensive in the long run.

7. Roll Up Refrigeration System - Roll up Refrigeration Systems are a lot like Penthouse Refrigeration Systems except they are rolled up to an opening in the side of the walk-in and attached to the unit. One difference is that even though the evaporator coil is located outside the unit it takes up shelf space inside the walk-in because shelving should not be installed in front of the unit. A licensed refrigeration technician will be needed to install the refrigeration system.

Now that you know all about these units don’t let it be confusing. To simplify the selection of refrigeration system, first decide whether allowing the condensing unit to dump heat into the building is unacceptable. If it is then a remote unit is the correct choice. Whether it is pre-assembled pre-charged should be decided by evaluating the difference in cost of having it done in the field or at the walk-in plant.

If dumping the heat inside the building is not a concern then choosing a self contained side mount or top mount refrigeration system verses a penthouse or rollup refrigeration unit should be decided by how important the space in the walk-in is to you. If space is important then a penthouse unit is the choice. If space is not a big consideration then side-mount, top mount or rollup unit may be the choice.

Whatever the refrigeation system you chose it is important to check the efficiency of the unit and the manufacturer’s warranty to make your final choice.

OUTDOOR APPLICATIONS:

Cooler and Freezers refrigeration system that are installed outdoors requires a winter kit. This kit provide a compressor cover, a crank case heater to keep the oil in the compressor warm so the compressor will operation properly in the cold weather, and a fan cycle control with keep the head pressure at the proper levels.

Outdoor Coolers and Freezer need to have rain roof installed to prevent water from leaking into the box. A rain roof can be of a single membrane polyester polyvinyl, chloride roof system with connectors and a drip cap for the door, or it can be metal flashing that installs over the roof seam to prevent water from leaking into the box.

WALK-IN COOLERS AND FREEZERS WITHOUT A FLOOR

Walk in coolers and freezers sometime come without a floor. Special precautions need to be taken to eliminate future problems. Walk-in coolers and freezers without a floor must be installed on a ground contact concrete floor. A cooler can be installed without insulating the floor and a thermal break under each wall panel but we recommend installing both. A freezer must be installed on an insulated concrete floor and must include a thermal break under each wall panel. An engineer or architect in your area will be required for the final design of your pad to meet local code approvals. If these precautions are taken you should have trouble free performance with you walk in floor.

MANUFACTUER:

No matter what walk-in system you buy one of the most important decisions is deciding which manufacturer to purchase from. There are a lot of manufacturers of walk-in coolers and freezers. They all have their niche in the walk-in industry. The amount of service they offer the end user varies. Look for a walk-in company that has these traits.

1. The company should have been in business for at least ten years.

2. The company should have a good web site explaining the items they offer and information about the company.

3. The company should answer the phone with a person not an answering device. Answering devices are for their convenience and not yours. Should you call you should always be able to talk to someone.

4. They should have clear quotes with itemized listing of the items provided.

5. They should be very informative and pleasant on the phone and treat you with interest and respect.

6. Their location and shipping cost need to be clearly spelled out. Shipping is a very important item in figuring up front cost of the project.

7. Check the warranty clearly so that you know what is covered should problems occur.

8. Get references of other customers.

9. Make sure they are National Sanitation Foundation and UL approved.

10. The company should specify how the walk-in is manufactured with the types of materials are used in its construction.

CONCLUSION:

Buying a walk-in cooler or freezer can be a large investment. Make sure you are totally informed before making a decision. Make sure you buy what you need and not what a salesperson is trying to sell you. Remember you are the one that will have to live with the walk-in you choose. Good Shopping.