The fundamentals of warewashing haven’t changed much—wash dishes, glasses and cutlery with a little bit of detergent, rinse and sanitize with either hot water (at 180°) or water with a chemical additive (at 140°). Though the basic principles remain the same, several manufacturers have developed new equipment to help save both time and energy.
Robert Doland, a foodservice consultant with New York City-based Jacobs | Doland believes that a large consideration is determining the “true cost” of a warewashing unit vs. the “initial cost.” “Some of the options that price certain full-featured machines out of a purchase are the very same that will go on to provide so much operational savings that, not only will they offset the cost of the option itself, they will most likely pay back the cost of the entire machine,” says Doland.
One of these options is an exhaust heat pump; it uses the machine’s exhaust heat to increase the temperature of incoming water. Hobart’s AM Select Ventless is the first door-type machine with such a built-in energy recovery system. Heat generated by the dishwasher is recycled through the machine to raise the temperature of incoming water. The overall effect is that less energy is required to heat water to the required wash and sanitize temperatures. “Plus, the energy recovery system harnesses the existing heat and steam generated by the machine that otherwise would have escaped when the door was opened,” explains Carrie Hoff, product line manager for Hobart.
The Hobart machine also alleviates the challenge of positioning the dish room. High-temp machines (180° sanitizing) have to be tied into building ductwork systems to vent the heat and humidity generated. Even 140° sanitizing cycle machines should be vented. Hoff adds that since there is no vent “there is no need for ductwork for the ventilation hood, making it easy to install the units where it is most convenient.”
For larger scale operations requiring flight-type machines, Champion Industries has developed the Heat Recovery with TempSure system on their EE-Series. With these features, the dishwasher can be connected to a cold water supply and still reach the appropriate wash and sanitize temperatures. The Heat Recovery System raises the temperature of incoming water from 60° to 110° without the need for any hot water. But what if the incoming water is less than 60°?
Champion’s TempSure system works with the Heat Recovery System to ensure that no matter what the water temperature, a safe cleaning temperature will be reached. This can impact LEED certification. According to Suzanne Painter-Supplee, director of consultant services for Champion Industries, energy for a hot water heater is regulated energy—the more energy used for heating water, the fewer LEED points can be earned. The cold water feed on the TempSure dishwasher reduces the required size of the hot water heater, lowering the amount of energy necessary for heating hot water.
On some of its undercounter series of dishwashers, Meiko is offering an Integrated Reverse Osmosis water filtering feature. The rinse water is passed through a dual-stage water filter that strips out minerals and chlorine. The purity of the rinse water eliminates the need for rinse-aid additives and the chore of polishing stemware and cutlery.
Doland also recommends that warewasher buyers seek models with high-efficiency spray nozzles and “smart” idle controls that allow the machine to use less energy in between wash cycles.