Washing dishes by hand, in a three-compartment sink, is a slow and labor-intensive process. Additionally, it is difficult to control important factors such as water temperature, chemical concentration, and immersion time. Unclean dishes create a bad impression and can be unsafe. Commercial dishwashers eliminate the need to wash dishes manually. They provide more reliable cleaning and sanitizing in less time with much less labor. Size, price, and configuration vary dramatically, and your choice will depend on the availability of space, your hot water supply, menu, and the volume of dishes to be washed. There are a wide variety of types and configurations available for all applications including specialty units.
How to Choose the Right Commercial Dishwasher
Initial Considerations
A preliminary step when selecting a commercial dishwasher is to evaluate some key factors in your foodservice operation:
Available Space – Common dish room equipment includes a commercial dishwasher, pot sink, drain boards, and drying racks. Consultants generally recommend about 5 square feet of dish room space for every seat in the front-of-the-house. A 100-seat dining room needs about 500 square feet of space (e.g., a room of about 20’x25’). If you are short on space, you may have fewer choices.
Electrical Service – Dishwashers commonly require either 120V or 208V service depending on the type. While any licensed electrician can install the service you need, installation is an initial cost that should be factored into your buying decision. Additionally, check the utility rates in your area. Electricity costs may have an impact on your buying decision.
Hot Water – Determine whether your facility has a constant supply of sufficiently hot water. Additionally, check the water rates in your area. In drought prone areas, water utility costs can be high. The availability and cost of hot water can be a factor when deciding what kind of dishwasher to purchase. Gas or electric booster heaters and holding tanks can be added to provide optimal temperature and water flow, but the additional expense must be considered.
Menu – How soiled are your dishes? Are you washing light soil from a menu that features soups, salads, sandwiches, and lighter fare? Or are you washing heavy soil from a menu that features a large amount of melted cheese, fatty meats, fried foods, and/or melted sugar. Some types of dishwashers are better suited for heavily soiled dishes.
Capacity – How many racks of dishes per hour do you need to process? Multiply the number of meals served per hour times the average number of dishes per meal. That will tell you how many dishes per hour you need to wash. Divide that by 20 to determine racks per hour.
High Temp vs. Low Temp
Consider which is best for you. Talk to your sales professional. High temperature dishwashers rely on hot water (180° to 195°F) to sanitize dishes. Low temperature dishwashers rely on temperatures as low as 120°F and use chlorine-based chemicals to sanitize dishes.
Some Advantages of High Temp Dishwashers
- No chemical sanitizers
- Dishes dry more quickly
- Use less water
Some Advantages of Low Temp Dishmachines
- Typically use hot tap water straight out of the facility’s main hot water supply
- Require less energy to heat water
- Initial purchase price is typically lower than high temp machines
Manufacturers such as Champion, CMA Dishmachines, Hobart, Jackson, and Moyer Diebel all offer a variety of high and low temp models.
Types of Dishwashers
Undercounter & Underbar – Undercounter dishwashers may look very similar to the consumer models found in many homes, but they are more powerful and designed for the rigors of commercial use. Most feature a door that tilts open from the front. They rely on standard commercial dish racks that are loaded in and out of the machine manually. They are ideal for small operations like coffee shops and kiosks. They are also ideal under the bar. They eliminate the need to wash dishes by hand and minimize the need for bartenders to transport glassware to and from the kitchen for washing. Available in both high and low temp models, high temp underbar machines often feature a heat reclamation system to keep steam and water vapor from escaping into the customer area when the door is opened. They can typically do about 30 racks per hour. Manufacturers such as Champion, CMA Dishmachines, Hobart, Jackson, and Moyer Diebel offer undercounter models.
Door Rack / Type – If you need more capacity, but don’t have a lot of extra floor space to work with, then a Door / Rack Type dishwasher is often the best choice. They are better for medium sized operations. Most are designed to process a single rack of dishes at a time. Instead of tilting out, the doors lift up and out of the way. Many can be loaded from either the front or the side and they can be placed between two dish tables or in a corner. Due to the additional vertical dimension, door / rack type dishwashers can often accommodate larger stock pots and sheet pans that wouldn’t fit in an undercounter. Available in high temp or low temp models, they typically process 30 to 60 racks per hour. Manufacturers such as Champion, CMA Dishmachines, Hobart, Jackson, and Moyer Diebel offer door /rack type dishwashers.
Rack Conveyors – Rack conveyors have a larger footprint and are for high volume dishwashing. They are good for large restaurants, cafeterias, and other high-volume venues. Installed between two dish tables, the wash chamber features a conveyor belt with strip doors on both ends. When a rack of dishes is slid a few inches into the machine, it triggers the wash pump and engages the conveyor belt. The conveyor carries the racks through the machine. They emerge from the other end, washed, rinsed, and sanitized. Rack conveyor machines are available with single or multiple tanks. In general, the more tanks, the faster the machine can process and clean dishes. Most rack conveyors are high temp machines, but low temp models are available. They can process between 200 and 350 racks per hour. Manufacturers such as Champion, CMA Dishmachines, Hobart, Jackson, and Moyer Diebel offer rack conveyors.
Flight Type Machines – Flight type machines have a very large footprint and are for large hotels, casinos, universities, and other high-volume operations that have a constant flow of dirty dishes. They feature a continuously advancing conveyor belt. They do not use dishracks. Instead, the conveyor surface features vertical pegs that allow operators to load dishware, glassware, and cooking ware directly onto the conveyor belt (flat racks or baskets are used for silverware and other small utensils). To keep the conveyor moving, clean dishes must be removed from the belt or it will pause until they are. Flight type machines commonly include a blower system to dry dishes after the rinse cycle. Conveyor belts range from 21 to 60 inches wide and the wider the belt, the higher the capacity. Smaller units can easily double the output of a rack conveyor, and larger units can process up to 24,000 dishes per hour, the equivalent of 1,200 racks per hour. Manufacturers such as Champion, Hobart, and Jackson offer flight type dishwashers.
Energy and Water Efficiency
Energy Star certified dishwashers are about 40% more energy efficient (and 50% more water efficient) than standard models. Eligible products include both high and low temperature stationary rack machines and conveyor type machines. According to Energy Star, a qualifying dishwasher can save operators an average of about $1500 annually, or about $19,000 over the life of the dishwasher. Manufacturers such as Champion, CMA Dishmachines, Hobart, and Jackson offer Energy Star rated models.
Some modern dishwashers feature heat reclamation systems. These systems capture heat exhaust and reuse it to maintain wash temperatures. They also eliminate the need for a Type II hood to remove steam and heat. Further, some modern dishwashers feature insulated wash chambers to retain heat and keep exterior surfaces cool to the touch.
Specialty Machines
Glasswashers – Typically for underbar use, glasswashers feature an open front with strip curtains and a slowly rotating platform or carousel. Glasses placed on the platform are carried through the strip curtains into the rear of the machine where they are washed, rinsed, and sanitized. When they reemerge on the other side, they are clean. Carousel type glass washers eliminate the need for racks and can provide a continuous supply of 800 to 1,400 glasses per hour. Manufacturers such as Champion, CMA Dishmachines, and Jackson offer carousel type glass washers.
Bakery and Pot Dishwashers – Similar to door / rack type machines, they are sized to hold large numbers of full sized sheet pans standing on end. They are for bakeries and operations that need to process large numbers of dirty sheet pans. Similar units are available for washing large stock pots and items that are too tall to fit into a standard dishwasher.
Conclusion
Each operation has its own unique dishwashing needs and challenges. Manufacturers such as Champion, CMA Dishmachines, Hobart, Jackson, and Moyer Diebel offer a wide variety of dishwashers that can solve many problems such as utility costs, space limitations, capacity demands, and budget. A Kitchen Spot expert can help you evaluate your operational needs and provide advice about all the various models and features to choose from.