KEEP IT CLEAN: It has never been easier to keep your forks, knives, dishes and glasses sparkling clean.
Something new and revolutionary is happening in warewashing equipment. It still may look pretty much the same, but the equipment is more energy efficient than ever before. Here's why: At least three European dishwasher manufacturers have recently come to the U.S. market. Each has products similar in size and capacity to those of their American counterparts. Each has a lot of similar features, but their point of difference is energy conservation. The Europeans have long demanded machines that use less electric and water because energy and water costs are higher than in the U.S.
To reduce operating costs, some of these European manufacturers have insulated their machines, which is an effective way to keep heat inside the tanks. Others have devised ways to reduce hot water consumption through engineered sensors on spray nozzles.
Interestingly, one of the best new water saving devices has come from a major American manufacturer, which has developed a high-temperature, final-rinse spray nozzle that uses far less water than other contemporary nozzles. The benefits are lower water consumption and much lower wattage electrical elements needed to heat the water. A large foodservice operation is likely to save thousands of dollars in annual operating costs from these new features.
Some warewashing basics
There are three basic types of foodservice dishwashers. Very small operations may be able to use an undercounter machine that generally has a realistic washing capacity of about 40 to 50 full place settings per hour. The commercial undercounter dishwasher looks, at first glance, quite similar to a residential style unit. The commercial unit, however, is much more powerful and faster than its residential counterpart. Commercial undercounter machine cycles vary from the slowest machines, which do their job in just over three minutes, to the fastest, which do the job in 90 seconds. Don't try to use a domestic model in your commercial operation because it will not meet the strict sanitation codes required.
The next step up in dishwasher size is the door-type, or full-height, single-rack machine. They wash and rinse a rack of dishes in a little over a minute. The rack machine can process about 90 to 110 place settings per hour and is suitable for a small-to medium-size foodservice operation. The typical door-type machine fits in a footprint approximately 24 inches square. The machines being made today also conserve water using only, in many cases, 1.2 gallons of fresh water per cycle. Most manufacturers make their door-type units in either a straight or a corner configuration.
For larger operations, rack conveyor machines start in size where the door-type machines leave off, and go up to models that can clean several hundred place settings per hour. Most manufacturers offer a wide array of conveyor machines that are based upon different combinations of several standard modules. All machines start with a basic wash tank and then add other modules that may be beneficial, depending upon the specifics of your operation.
The next step up to higher capacity and better performance is the addition of a rinse tank or an extended wash tank. Machines without a rinse tank to recirculate rinse water typically use more water than those with a recirculating rinse. All machines have a fresh water final sanitizing rinse. Conveyor machines range in length from 44 inches to about 10 feet and can be built in a circular configuration for some high-volume operations.
Flight-type machines are a fourth dishwasher style that is generally too large for restaurants. Flight machines differ from their conveyor counterparts in that dishes are loaded directly onto pegs built into the machine. They are generally used in institutions and extremely high-volume operations.
The amount of dishes to be washed will be the major factor in determining the type of dishwasher to purchase. When looking at machine capacities, you need to understand and decode the manufacturers' ratings. Most manufacturers advertise the capacity of their machines by the number of racks per hour they can handle based on their NSF (National Sanitation Foundation) listing.
The ratings for door-type machines are about 40 to 60 racks per hour, while conveyor machines start at 200 racks per hour. Those ratings can be misleading because they are computed mathematically and are not based on actual machine operation that must allow for loading and unloading the machine. In other words, if a machine is rated at 200 racks per hour, you should be able to wash about 140 racks per hour.
The same is true for manufacturers' claimed capacity of dishes per hour. Actual washed dishes per hour may be even less than 70% since the claims are usually based on a small dish or glass that fits a 20 - by 20-inch rack.
Once the size and style of machine have been determined, there are several other initial purchase decisions to make. Using low temperature or chemical sanitizermachines is one way to save on hot water costs and reduce some ventilation requirements. Chemical sanitizing machines use a sanitizing chemical in the final rinse rather than 180° F water to do the job. Manufacturers tout chemical sanitizing machines because of their low energy consumption. You must weigh the cost of the sanitizing agent against your energy costs. Also, be aware that a high-temperature final rinse dries your dishware faster than a chemical sanitizer.
High-temperature machines are also better able to break down animal fats, grease and lipstick on glassware and dishes. Don't forget, no matter which type of high temperature warewasher you buy, you'll still need 180°F water for the final rinse. You'll also need a high-wattage electric booster heater, steam heat or gas. The difference now is that the total electric load can be lower and the savings can go right to the bottom line.
Dan Bendall is a principal of FoodStrategy, a Maryland-based consulting firm specializing in planning foodservice facilities. He is also a member of Foodservice Consultants Society International (FCSI).