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Flight-type machines are a fourth dishwasher style, but they are generally used in institutions and extremely high volume operations for mass feeding.  

Using low-temperature or chemical sanitizer machines is one way to save on hot water costs and reduce some ventilation requirements. These machines are sometimes mislabeled as cold water machines, but all dishwashers must use hot water. The low-temperature machines just don’t use the super hot 180° rinse water.  Instead, they use a sanitizing chemical in the final rinse to do the job.

As an operator you must weigh the cost of the sanitizing agent against the energy savings. Also, be aware that a benefit of a high-temperature final rinse is a dishware that dries quickly. High-temperature machines are also better able to break down animal fats and grease as well as lipstick on glassware and dishes.    

In recent years, several manufacturers have developed machines that reduce water consumption by 30 to 60 percent over older similar sized machines. Except for the initial filling of the wash tanks at the beginning of the shift, the only fresh water used in dishwashers is in the final rinse.

One way these machines save water is with a simple innovation of changing the size of the water droplets in the final rinse portion of the wash. It was found that using a different size water droplet significantly increased the heat transfer to dishware, aiding in sanitation and reduced water consumption. The droplet size and scientifically designed spray patterns have been the cornerstones to reducing typical booster heater sizes by almost half in many cases.  

The booster heater is used to heat water from 140° to a sanitizing temperature of 180°.  Cutting booster heater size is huge since the electrical loads on many older machines are 50 kilowatts or more. Reducing that load to 30 kilowatts or less yields a significant cost savings.

Knowing your operation’s needs and what is available on the market will help you choose the right capacity dishwasher for your operation. Be sure to ask and compare energy and water usage, not just initial cost of the equipment. Look for the water and energy saving features mentioned here. Then, when you get your new machine, take care of it. Perform regular preventive maintenance, including deliming.  

Dan Bendall is a principal of FoodStrategy, a firm specializing in planning foodservice facilities.