Maintenance of refrigeration, cold rooms and freezers
Most refrigerators and walk-in freezers seem virtually indestructible and trouble-free, but you’ll get a longer life by following these safety and maintenance tips. Clean door seals and hinges regularly. Door gaskets, made of rubber, can rot more easily if they are covered in food or dirt, weakening their sealing properties. They can be safely cleaned with a solution of baking soda and warm water. The hinges can be rubbed with a little Vaseline to keep them working well. Dirty coils force the refrigerator to run hotter, shortening the life of the compressor motor. They should be cleaned every 90 days, preferably with an industrial vacuum.
Entry floors can be cleaned with a damp mop, but should never be hosed down. Too much water can get into the seals between the floor panels and damage the insulation. A refrigerator only works as well as the air that can circulate around its contents. Stacking food containers so there isn’t an inch of free space around them doesn’t help. Also try to keep containers (especially cardboard ones) from touching cabinet walls. They can freeze and adhere to the walls, damaging both the product and the wall. Use a good rotation system: first in, first out (FIFO) is preferable. Or put colored dots on food packages, a different color for each day of the week, so everyone in your kitchen knows how long each item has been in the fridge.
WALK-IN REFRIGERATORS AND FREEZERS
A walk-in freezer is just what its name suggests: a fridge big enough to fit inside. It can be as small as a closet or as large as a good-sized room, but its primary purpose is to provide refrigerated storage for large amounts of food in one central area. Experts suggest your operation needs walk-in service when your refrigeration needs exceed 80 cubic feet, or if you serve more than 250 meals per day. Again, you’ll need to determine how much you need to store, what container sizes the storage space should accommodate, and the maximum number of products you’ll want to keep on hand. The only way to use the entrance space wisely is to equip it with shelves, arranged in sections. Exactly how many square feet do you need? The simplest formula is to figure 1 to 1.5 cubic feet of storage space for each meal you serve per day. Another basic calculation: Take the total number of linear feet of shelving you’ve decided you’ll need (A) and divide it by the number of shelves (B) you can fit in each section.
This will give you the number of linear feet per section (C). To this number (C), add 40 to 50 percent (1.40 or 1.50) to cover “overflow” volume increases, wasted space, and bulky items or loose products. This will give you an estimate of the total linear footage (D) needed. However, linear footage is not enough. Since the shelves are three-dimensional, you need to calculate the square footage. So multiply (D) by the depth of each shelf (E) to get the total number of square feet (F). Finally, double the figure (F) to compensate for the hallway space. About half of the cold room space is aisle space. Another popular formula is to calculate that for every 28 to 30 pounds of food you store, you’ll need 1 cubic foot of space. When you get that number, multiply it by 2.5. (The 2.5 factor means that only 40 percent of your storage space will be used as storage space; the other 60 percent is aisles and space between products.)
The result is the size of the refrigerated storage area you will need. For a cold room, simply divide your cold room space by two. Larger kitchens, serving more than 400 meals a day, may need as many as three walk-in coolers for different temperature needs: one for produce (41 degrees Fahrenheit), one for meat and fish (33 to 38 degrees Fahrenheit), and one for for dairy products (32 to 41 degrees Fahrenheit). The walk-in is most often used to store bulk food. Since this often means getting carts or dollies in and out, the floor needs to be level with the kitchen floor.
This leveling is achieved through the use of strips (called soleras) that are applied to the floor. Refrigerators do not come as a single unit; are built on site. The walls, ceilings and floors are made of individual panels. Wall panels must be insulated with a rating of R-30, which means a thickness of 4 inches. They come in various lengths and widths, with 12-by-12-inch corner panels at 90-degree angles. They can be as short as 71?2 feet or as tall as 131?2 feet. The most common type of insulation inside the panels is polyurethane, and the exterior walls of the panels can be made of stainless steel, vinyl, or aluminum. Stainless steel is the most expensive and aluminum, because it is the least expensive, is the most popular choice. If the walk-in is an outdoor installation, aluminum is the most weather resistant.
The installer will ensure that the unit has interior lighting. Floor panels for dressing rooms are similar to wall panels. Load capacities of 600 pounds per square foot are the norm, but if you plan to store very heavy items (like beer kegs), a reinforced floor with a load capacity of up to 1,000 pounds per square foot can be purchased. The single-chamber refrigeration system is a more complex installation than a standard refrigerator, mainly because it is so much larger. It’s best to let professionals match the system (and its power requirements) to the dimensions of the chamber and its intended use, but it’s important to note that a chamber that is frequently accessed during the day will require a compressor with more power to maintain its internal temperature than one that is seldom accessed.
A 9 square foot walk-in would need at least a 2 horsepower compressor. The condenser unit is located at the top of the walk-in (directly above the evaporator) or up to 25 feet away, with lines connecting it to the walk-in. The latter, for obvious reasons, is known as a remote system and is required for larger than normal condensing units with capacities up to 7.5 horsepower. In a remote system, refrigerant must be added at the time of installation. For smaller walk-ins, there is also a plumbing setup called a quick coupler system, which ships from the factory fully charged with refrigerant. This definitely simplifies installation. However, you may need the added power of a remote system if your kitchen has any of these drains on cabinet cooling capacity: frequent door openings, glass display doors, multiple doors per compartment, or a temperature kitchen environment close to 90 degrees. Fahrenheit.
Modern walk-ins sometimes offer a frozen food section in addition to the usual cooler space. There are pros and cons to this concept. You can ease the load on the freezer, because it’s already located inside a cold air space; but it also can’t help but reduce overall usable space, because it requires a separate door. You can also order your walk-in closet with a separate reach section that has its own door and shelves. Although this can save the cost of purchasing a separate built-in cabinet, some critics claim that a built-in cabinet is not designed to do built-in cabinet work, such as storing uncovered desserts. Do you really want them in the same environment as cartons of lettuce and other bulk storage items? There may be cleanliness or food quality factors to consider.
Doors should open outward, not into the cooler itself. The standard door opening is 34 by 78 inches. Several door features are important to the proper operation of the door. These include: A heavy-duty door closer. Self-closing door hinges with cam lift. If the door can be opened beyond a 90 degree angle, the cam will hold it open. High resistance stainless steel threshold. It is installed on the galvanized channel of the door frame. A pull-type door handle, with a cylinder door lock and space to use a separate padlock if required. Pressure sensitive vents, which prevent vacuum build-up when opening and closing the door. An interior security release so no one can get (accidentally or otherwise) locked inside the cooler.
Other smart features that can be ordered for cameras include: A thermometer (designed for outdoor use, but mounted inside the cooler) with a range of 40 to 60 degrees Fahrenheit. A monitoring and recording system that keeps a printout of refrigeration temperature or downloads to a computer. Glass, full-length door panels (such as those in supermarkets and convenience stores), sometimes called merchandising doors, either hinged or sliding. High resistance plastic strip curtains inside the door. (One manufacturer claims 40 percent energy savings with this feature.)
A pedal, which allows you to open the door by pressing a pedal or lever with your foot when both hands are occupied. Three-way interior lighting, which can be turned on from the outside or from inside the cooler, with a power indicator light on the outside. Inside, the light itself should be a vapor-proof bulb with an unbreakable globe and shield. When space is at a premium, consider whether it is practical to install an outdoor unit with a walk-in closet. This is an inexpensive way to add space without increasing the size of your kitchen, and you can purchase ready-made freestanding structures with electricity and refrigeration systems installed. They come in standard sizes from 8 to 12 feet wide and up to 50 feet long, in 1-foot increments.
They range in height from 7.5 to 9.5 feet. Look for a unit with a sloped, weather-resistant roof, a weather cover, and a fully insulated floor. Outdoor walk-in closets are about half the price of installing an indoor kitchen walk-in closet, so this is a money-saving idea if it works in your location. If your demands for walking space are seasonal, consider renting a refrigerated trailer, available in most metropolitan areas on a weekly or monthly basis. They can instantly provide 2,000 cubic feet of additional storage space, which can be maintained at any temperature from 40 to 80 degrees Fahrenheit. They use basic three-phase electricity of 60 amps and 230 volts. Ask if the lease includes connection to your site and service if something goes wrong.