RECIRCULATING CHEMICAL-SANITIZING WASHING MACHINE

Abstract

A method for operating a recirculating chemical-sanitizing dishwasher includes filling a wash tank of the dishwasher with water, and performing a first cycle of washing by circulating the water through a wash chamber of the dishwasher. A partial drain is performed of a first amount of water from the wash tank, and new water (for example, rinse water) is added to the wash tank for a second amount of water approximately equal to the first amount. A second cycle of washing is performed by circulating the water through the wash chamber of the dishwasher.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This patent application claims the benefit of U.S. Provisional Patent Application No. 63/328,200, filed Apr. 6, 2022, which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

This application relates generally to washing machines and more particularly to a method and apparatus for recirculating water in a washing machine such as a dishwasher.

BACKGROUND

A dishwasher, also referred to as a warewasher or warewashing machine, is a machine for automatically cleaning articles, such as dishes, trays, laboratory equipment, dinnerware, and kitchenware. A common domestic dishwasher is an undercounter unit intended to be installed under a kitchen counter. Other types of dishwasher include industrial or commercial dishwashers for use in restaurants, hotels, and other commercial establishments with food services.

Common types of dishwashers include dump-and-fill type machines and recirculating type machines. Dump-and-fill type machines drain completely between washing and rinsing cycles, whereas recirculating type machines reuse wash water from cycle to cycle. Dump-and-fill type machines typically use a longer duration for cleaning and inherently waste water and energy, and recirculating type machines can leave residual detergent or soil and may require additional heating and machine complexity to maintain water temperature.

What is needed is an improved dishwasher that provides cleaner dishes, reduced cycle times and minimal additional heating or machine complexity.

SUMMARY

A system and method for operating a recirculating chemical-sanitizing dishwasher includes filling a wash tank of the dishwasher with water, and performing a first cycle of washing by circulating the water through a wash chamber of the dishwasher. A partial drain is performed of a first amount of water from the bottom of the wash tank, and new water is injected into the wash tank in a second amount of water approximately equal to the first amount. A second cycle of washing is performed by circulating the water through the wash chamber of the dishwasher.

In one example, the first amount of water is approximately 20 to 30 percent of capacity of the wash tank. In some examples, the mini drain is performed several times over several cycles, and the wash tank is subsequently completely drained and refilled before proceeding with a next cycle.

This summary is an overview of some of the teachings of the present application and not intended to be an exclusive or exhaustive treatment of the present subject matter. Further details about the present subject matter are found in the detailed description and appended claims. The scope of the present invention is defined by the appended claims and their legal equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate generally, by way of example, various embodiments discussed in the present document. The drawings are for illustrative purposes only and may not be to scale.

FIG. 1A illustrates one example of a recirculating wash dish machine.

FIG. 1B illustrates one example of a dump-and-fill dish machine

FIGS. 2A-2C illustrate a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter.

FIG. 3 is a schematic diagram illustrating a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter.

FIG. 4 illustrates a user menu for operation of machine setpoints for a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter.

FIG. 5 illustrates a graphical diagram for washing sequence step for a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter.

FIG. 6 is a flow chart illustrating a method for operating a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter.

DETAILED DESCRIPTION

The following detailed description of the present subject matter refers to subject matter in the accompanying drawings which show, by way of illustration, specific aspects and embodiments in which the present subject matter may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present subject matter. References to “an”, “one”, or “various” embodiments in this disclosure are not necessarily to the same embodiment, and such references contemplate more than one embodiment. The scope of the present invention is defined by the appended claims, along with the full scope of legal equivalents to which such claims are entitled.

This application discusses, among other things, a chemical-sanitizing dish machine that utilizes a recirculating wash to save water, energy, and chemistry while maintaining proper wash water heat by draining a small portion of wash water prior to the rinse step (referred to herein as a partial drain or a mini-drain), running frequent cycles where the tank fully drains, and utilizing a small tank size.

The present system, apparatus and method provides a low-temperature, chemical sanitizing dish machine utilizing digital controls that allow operational modes that save water and energy and decrease total wash cycle time, to replace the current dump-and-fill low-temp dish machine, which is inherently wasteful in terms of water, energy, and chemistry. The present system enables running the machine in a recirculating mode to reuse wash water from cycle to cycle while maintaining wash temperature without a dedicated heat source, including preserving wash temperature by partially draining a portion of wash water prior to rinse introduction.

According to various embodiments, a recirculating system is provided where the tank is not fully drained every cycle, and the rinse is introduced through a separate set of rinse nozzles from a freshwater source. The present system maintains wash tank temp by utilizing a smaller tank size (approximately 2 gallons in an embodiment) and displaces a large amount of this with rinse water (approximately 0.75 gallons/rack in an embodiment). Additionally, a small portion of cooler wash water is drained (a partial drain or mini drain) from the bottom of the tank prior to the rinse being introduced. In some embodiments, the partial drain may be performed from other portions of the tank. In some embodiments, the tank is fully drained approximately once every 5 cycles to refresh the tank and manage food soil loads. Since these refresh cycles will introduce higher water volumes into the machine that need to be concentrated with additional chemistry, the present system may introduce a detergent boost on the cycle immediately following the tank refresh. This boost automatically lengthens the detergent dispense time by an amount proportional to the extra time that the fill valve is open during the refresh.

Various embodiments provide a system for operating a recirculating chemical-sanitizing dishwasher. The system includes a dishwasher with a wash tank, wash chamber and drain. A wash tank of the dishwasher is filled with water, and a first cycle of washing is performed by circulating the water through a wash chamber of the dishwasher. A partial drain is performed of a first amount of water from the bottom of the wash tank, and new water is injected into the wash tank in a second amount of water approximately equal to the first amount. A second cycle of washing is performed by circulating the water through the wash chamber of the dishwasher. In one example, the first amount of water is approximately 20 to 30 percent of capacity of the wash tank. In some examples, the partial drain is performed several times over several cycles, and the wash tank is subsequently completely drained and refilled before proceeding with a next cycle.

FIGS. 1A-1B illustrate examples of dump-and-fill and recirculating washing machines. FIG. 1A illustrates an example of a recirculating dish machine type with rotating rinse arms, rotating wash arms, a wash tank strainer, an overflow pipe, a pump inlet strainer, a wash pump, and a drain. The recirculating dish machine performs a recirculating cleaning sequence with fresh water rinse, including a wash step and a rinse step. In the wash step, the wash pump recirculates wash water with detergent from the wash tank through wash arms and over dishes. The wash water is reused from cycle to cycle. In the rinse step, incoming fresh water at line pressure is injected with rinse aid and sanitizer if applicable, and sprayed through the rinse arms over the dishes. Typically, for high temperature recirculating machines, heaters are required to maintain wash temperature from cycle to cycle, and rinse water from a previous cycle is collected in the wash tank and displaces a like amount down the drain.

FIG. 1B illustrates an example of a dump-and-fill dish machine type with incoming water, rotating wash and rinse arms, a pump inlet strainer, a sump, a drain stopper/overflow pipe, a drain pan strainer, a wash pump and a drain. The dump-and-fill dish machine performs a cleaning sequence including a wash step, a drain step, a fill step and a rinse step. In the wash step, the wash pump recirculates wash water with detergent from the wash tank through the wash arms and over the dishes. In the drain step, water and soils are drained completely from the machine. In the fill step, the machine fills with fresh water and is dosed with rinse aid and sanitizer. In the rinse step, the pump recirculates rinse water from the tank through the wash arms and over the dishes. Rinse water from the previous cycle remains in the machine and is used as wash water for the next cycle. Typically for low temperature chemical sanitizing dump-and-fill machines incoming hot water each cycle maintains a relatively warm temperature from approximately 120 to 140 F.

Benefits of the recirculating machine of FIG. 1A include a faster cycle time because there is no drain and fill in the middle of a cycle, no carry-over of detergent and/or soils to dishes at the end of a cycle since wash water and rinse water are completely separated, and separate mechanical systems for wash and rinse allowing for optimization for both wash and rinse. Drawbacks of the recirculating machine of FIG. 1A include recirculating dirty wash water over dishes which requires periodic stopping of operating to remove soils and draining and refilling the tank, low incoming water pressor reduces the quality of the rinse, low temperature of incoming water can cause low rinse temperatures as the booster heater cannot recover fast enough to maintain temperature, and relatively high complexity.

Benefits of the dump-and-fill machine of FIG. 1B include that soils are drained from the machine after each wash sequence, the pumped rinse through the wash arms adds to cleaning action, chlorine from the rinse in the wash step can improve cleaning, and effective rinse action is not reliant on incoming water pressure. Drawbacks of the dump-and-fill machine of FIG. 1B include residual detergent or soils on dishes after the rinse step if not completely drained after the wash step, incoming water temperature controls temperature of the rinse water, and a long duration between wash cycles reduces temperature of wash water.

FIGS. 2A-2C illustrate a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter. FIG. 2A illustrates advantages of the recirculating chemical-sanitizing dishwasher of the present subject matter when compared to traditional dump-and-fill and recirculating machines. The recirculating chemical-sanitizing dishwasher combines benefits of both traditional dump-and-fill and recirculating machines without the drawbacks listed above. The present recirculating chemical-sanitizing dishwasher recirculates water with frequent dumps or partial drains to maintain temperature and lower food soil resulting in cleaner dishes. Thus, the present recirculating chemical-sanitizing dishwasher provides a simple design that is easy to service, is affordable, can handle heavy food soil loads, does not require a heater, lowers water consumption, uses shorter cycle times, and utilizes a fresh water rinse. Detergent chemistries may be dispensed in various ways according to various embodiments. In various embodiments, the present subject matter is suited for solid detergent chemistries. In various embodiments, the present subject matter is suited for liquid detergent chemistries. In various embodiments, an amount of injected detergent is proportional to the amount of the injected water, to maintain a level of detergent in the water. In one embodiment, the amount of injected detergent is scaled to the amount of water injected.

FIG. 2B illustrates an overview of an embodiment of the recirculating chemical-sanitizing dishwasher of the present subject matter. The dishwasher includes a display, an input/output (I/O) board, a power supply, swing-out doors, and dispensing and accessory connections. The present dishwasher provides a low-temperature innovation using a novel control system. The control system includes a digital I/O board with flexible operation and enhanced features, improved troubleshooting, and enabling digital strategy. The present recirculating chemical-sanitizing dishwasher further includes an improved display with a simple user interface. In addition, the present recirculating chemical-sanitizing dishwasher provides for improved machine operation including partial drains that reduce water usage by over 25%, result in a 30% reduction in cycle time, improved startup and shutdown sequences, and an automated delime sequence. The recirculating chemical-sanitizing dishwasher includes a redesigned control head with swing-out doors for easier access, a large footprint for easy service, and fewer components that traditional recirculating machines.

FIG. 2C illustrates further details of an embodiment of the recirculating chemical-sanitizing dishwasher of the present subject matter. The recirculating chemical-sanitizing dishwasher includes a new dispensing system with diaphragm pumps to replace traditional squeeze tubes, support for both liquid and solid detergent chemistries, and provides for warning and/or alarms. The recirculating chemical-sanitizing dishwasher includes an improved inlet plumbing system including flexible “jiffy” hoses with swivel fittings providing for improved field service and flexible installation. The recirculating chemical-sanitizing dishwasher also includes a fresh water rinse system including a halo design to eliminate moving parts, the fresh water rinse decreasing detergent carryover between cycles or steps.

FIG. 3 is a schematic diagram illustrating a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter. The recirculating chemical-sanitizing dishwasher includes a drain connection A, an electrical connection B, and a water inlet C, in various embodiments. According to various embodiments, the partial drain allows the old, colder water to be controllably released per cycle, so the machine stays full as the new water cycles into the machine. In some embodiments, the machine performs a complete dump of all water every 5 cycles in which case the full drain cycle will drain all water from the tank.

FIG. 4 illustrates a user menu for operation of machine setpoints for a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter. From a service menu, a user may navigate to a machine setpoints menu to adjust machine parameters. In various embodiments, fill time adjusts the amount of time the machine fills on startup and following a full drain of the tank. The partial drain time is the amount of time the drain is open during an exemplary (non-full) drain cycle, in various embodiments. According to various embodiments, water drained during the partial drain is approximately equal to the amount of water added during the rinse step. In various embodiments, the amount of water drained during a partial drain may be varied.

FIG. 5 illustrates a graphical diagram for washing sequence step for a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter. Unlike prior wash machines, the present recirculating chemical-sanitizing dishwasher operates as a recirculating machine with frequent full tank drains. Wash water is maintained in the tank from cycle to cycle until a full drain cycle is run, in various embodiments. In some embodiments, full drain frequency defaults to every 5 cycles, but is adjustable from every cycle to every 10^th cycle. In various embodiments, a freshwater rinse is introduced into the machine via the incoming water line (from approximately 15-25 pounds per square inch or psi). A short partial drain (at a default time of 1.4 seconds, which is adjustable) occurs following the wash step during exemplary cycles, in various embodiments. This partial drain flushes a portion of dirty wash tank water which is then replaced by the incoming freshwater rinse, improving the machine performance without requiring additional heating, in various embodiments.

FIG. 6 is a flow chart illustrating a method for operating a recirculating chemical-sanitizing dishwasher, according to various embodiments of the present subject matter. The method 600 for operating a recirculating chemical-sanitizing dishwasher includes filling a wash tank of the dishwasher with water at step 602, and performing a first cycle of washing by circulating the water through a wash chamber of the dishwasher at step 604. At step 606, a partial drain is performed of a first amount of water from the bottom of the wash tank, and new water is injected into the wash tank in a second amount of water approximately equal to the first amount at step 608. At step 610, a second cycle of washing is performed by circulating the water through the wash chamber of the dishwasher.

In various embodiments, adding additional water in a second amount includes adding rinse water. In various embodiments, adding additional water includes adding water directly to the wash tank. Persons of skill in the art will appreciate that a variety of ways to add water to the tank may be employed without departing from the scope of the present subject matter.

According to various embodiments, the first amount of water is approximately 20 to 30 percent of capacity of the wash tank. In some embodiments, the method further includes performing a partial drain of the first amount of water from the bottom of the wash tank, injecting new water into the wash tank in the second amount of water approximately equal to the first amount, and performing a third cycle of washing by circulating the water through the wash chamber of the dishwasher. The method also includes performing a partial drain of the first amount of water from the bottom of the wash tank, injecting new water into the wash tank in the second amount of water approximately equal to the first amount, and performing a fourth cycle of washing by circulating the water through the wash chamber of the dishwasher, in various embodiments. In some embodiments, the method further includes performing a full drain of a third amount of water from the bottom of the wash tank, the third amount approximately equal to capacity of the wash tank, injecting new water into the wash tank in a fourth amount of water approximately equal to the third amount, and performing a fifth cycle of washing by circulating the water through the wash chamber of the dishwasher.

In various embodiments, the present subject matter provides a washing sequence including:

• • a. a wash cycle where wash water containing detergent in the wash tank is recirculated via wash pump through the wash chamber;
  • b. A partial drain function where the drain ball is opened to drain a set volume (less than the entire volume) from the tank;
  • c. A full drain function where the drain ball is opened to drain the entire volume from the tank; and
  • d. A rinse drain function where the fill valve opens and supplies fresh water (dosed with rinse aid and sanitizer) at line pressure from house water supply equal in volume to the partial drain (or the tank volume in the case of a full drain). The water in the tank is not recirculated through the chamber via the wash pump in this step.

Those of skill in the art upon reading and understanding the present subject matter will appreciate that the order of steps and quantity of each step may vary without departing from the scope of the present subject matter.

In this application, a “dishwasher”, which can also be referred to as a dish machine, a warewasher or a warewashing machine, includes any type of wash machine that can use detergent for cleaning and/or sanitizing purposes. One example includes an undercounter dishwasher for washing dinnerware, flatware, pots and pans, cutlery, flatware, glasses, kitchenware, serving pans, trays, and so on. Commercial dishwashing equipment examples can also use the present subject matter. A dishwasher includes a washing tub formed by interior walls and a door of the dishwasher. In an example of the undercounter kitchen dishwasher, the door rotates up to about 90 degrees about a horizontal axis to switch between a fully closed state and to a fully open state. The door has an interior side and an exterior side that are both substantially vertical when the door is fully closed and substantially horizontal when the door is fully open.

A “cleaning cycle” can include other periods, such as one or more of a washing period, a rinsing period, and a drying period, depending on settings made by a user of the dishwasher. The door is opened at least once between two consecutive cleaning cycles to allow loading of the dishes and/or other objects to be cleaned and unloading of the cleaned dishes and/or other objects. “Cleaning” can include cleaning only, sanitizing only, or cleaning and sanitizing, depending on, for example, whether the solid detergent blocks are capable of cleaning only, sanitizing only, or cleaning and sanitizing. A “washing period” includes a period or operational mode that is intended for a cleaning mixture formed by water and detergent to be applied to the dishes and/or other objects. A “rinsing period” includes a period or operational mode that is intended for water, or water and a chemical rinsing aid and/or a chemical sanitizer, to be applied to the dishes and/or other objects. Some dishwashers (e.g., commercial dishwashers) may include a rinsing period that is primarily for sanitizing through heat and/or chemical means. A “drying period” includes a period or operational mode that is intended for the cleaned dishes and/or other objects to be dried by air flow and/or heat, without additional water and/or detergent applied. The dishwasher usually allows the user to choose whether to include the drying period in the cleaning cycle because the user can open the dishwasher door to allow the washed and rinsed dishes to dry naturally or remove the washed and rinsed dishes to another place for drying.

A batch of objects to be cleaned (for example, dishes) can be loaded into a tub of the dishwasher, typically including racks and utensil holders, to be cleaned in a cleaning cycle that include washing and rinsing periods. During the washing period, a cleaning mixture formed by water and dishwasher detergent is sprayed into the loaded tub to blast the dishes. Typically, the cleaning mixture is then drained before the rinsing period starts. During the rinsing period, water is sprayed into the washing chamber to remove residue of the cleaning mixture. After the rinsing period complete with the rinsing water being drained, the dishes can optionally be dried using air and/or heat during a drying period. A dishwasher may have various user-selectable settings for each cleaning cycle. The settings may define, for example, time, temperature, and repetition of each of the washing, rinsing, and drying period. The setting may also allow the user to choose which periods to include (e.g., rinsing only, drying only, rinsing and drying, or washing and rinsing without drying).

Application in a dishwasher is discussed as an example, but not a limitation, for the present subject matter. The present system for can be applied in any washing machine that sprays water that can be partially drained during a cleaning cycle.

Some non-limiting examples (Examples 1-5) of the present subject matter are provided as follows:

In Example 1, a method for operating a recirculating chemical-sanitizing dishwasher may include providing a tank of water in a wash tank of the dishwasher, using the tank of water for a first wash process of the dishwasher, partially draining a first amount of water from the tank of water in the wash tank, adding additional water to the wash tank in a second amount approximately equal to the first amount, thereby creating a partially refreshed tank of water, wherein the additional water does not include the water drained from the tank, and using the partially refreshed tank of water for another wash process of the dishwasher. In various embodiments the steps of partially draining, adding additional water, and using the partially refreshed tank of water can be repeated a number of times, such as 1 to 5 times. In various embodiments, the method includes fully draining the wash tank. In various embodiments, the method includes adding new water to refill the wash tank. In various embodiments, the method includes using a rinse process for adding additional water. In various embodiments, the method includes using a rinse process for adding new water.

In Example 2, the subject matter of Example 1 may optionally be configured to further include the first amount of water may approximately 20 to 30 percent of capacity of the wash tank.

In Example 3, the subject matter of any one or any combination of Examples 1 and 2 may optionally be configured to further include partially draining the first amount of water from the partially refreshed tank of water, injecting new water into the wash tank in the second amount approximately equal to the first amount, thereby creating a second partially refreshed tank of water, and circulating the second partially refreshed tank of water through the wash chamber of the dishwasher.

In Example 4, the subject matter of Example 3 may optionally be configured to further include partially draining the first amount of water from the second partially refreshed tank of water, injecting new water into the wash tank in the second amount approximately equal to the first amount, thereby creating a third partially refreshed tank of water, and circulating the third partially refreshed tank of water through the wash chamber of the dishwasher.

In Example 5, the subject matter of Example 4 may optionally be configured to further include draining a third amount of water from the third partially refreshed tank of water, the third amount approximately equal to capacity of the wash tank, injecting new water into the wash tank in a fourth amount of water approximately equal to the third amount, thereby creating a fully refreshed tank of water, and circulating the fully refreshed tank of water through the wash chamber of the dishwasher.

In Example 6, the subject matter of Example 1 may further include dispensing detergent in an amount relating to the amount of fresh water injected into the wash tank.

In Example 7, the subject matter of Example 6 may optionally be configured where the dispensing is performed using a solid detergent chemistry.

In Example 8, the subject matter of Example 6 may optionally be configured where the dispensing is performed using a liquid detergent chemistry.

In Example 9, the subject matter of Example 6 may optionally be configured where the amount of detergent is proportional to the amount of new water injected into the wash tank.

In Example 10, the subject matter of Example 1 may optionally be configured where adding the additional water includes using rinse water.

This application is intended to cover adaptations or variations of the present subject matter. It is to be understood that the above description is intended to be illustrative, and not restrictive. The scope of the present invention should be determined with reference to the appended claims, along with the full scope of legal equivalents to which such claims are entitled.

Claims

1. A method for operating a dishwasher, the method comprising:

providing a tank of water in a wash tank of the dishwasher;

using the tank of water for a first wash process of the dishwasher;

partially draining a first amount of water from the tank of water in the wash tank;

adding additional water to the wash tank in a second amount approximately equal to the first amount, thereby creating a partially refreshed tank of water, wherein the additional water does not include the water drained from the tank; and

using the partially refreshed tank of water for another wash process of the dishwasher.

2. The method of claim 1, wherein the first amount of water is approximately 20 to 30 percent of capacity of the wash tank.

3. The method of claim 1, further comprising:

partially draining the first amount of water from the partially refreshed tank of water;

injecting new water into the wash tank in the second amount approximately equal to the first amount, thereby creating a second partially refreshed tank of water; and

circulating the second partially refreshed tank of water through a wash chamber of the dishwasher.

4. The method of claim 3, further comprising:

partially draining the first amount of water from the second partially refreshed tank of water;

injecting new water into the wash tank in the second amount approximately equal to the first amount, thereby creating a third partially refreshed tank of water; and

circulating the third partially refreshed tank of water through the wash chamber of the dishwasher.

5. The method of claim 4, further comprising:

draining a third amount of water from the third partially refreshed tank of water, the third amount approximately equal to capacity of the wash tank;

injecting new water into the wash tank in a fourth amount of water approximately equal to the third amount, thereby creating a fully refreshed tank of water; and

circulating the fully refreshed tank of water through the wash chamber of the dishwasher.

6. The method of claim 1, further comprising:

dispensing detergent in an amount relating to the amount of fresh water injected into the wash tank.

7. The method of claim 6, wherein the dispensing is performed using a solid detergent chemistry.

8. The method of claim 6, wherein the dispensing is performed using a liquid detergent chemistry.

9. The method of claim 6, wherein the amount of detergent is proportional to the amount of new water injected into the wash tank.

10. The method of claim 1, wherein adding the additional water includes using rinse water.

11. A method for operating a dishwasher including a wash tank, a wash pump and a wash chamber, the method comprising:

performing a wash cycle where wash water containing detergent in the wash tank is recirculated via the wash pump through the wash chamber;

performing a partial drain function where a drain ball is opened to drain a set volume less than an entire volume from the wash tank; and

performing a rinse drain function including opening a fill valve to supply fresh water dosed with rinse aid and detergent at line pressure from a water supply approximately equal to the set volume.

12. The method of claim 11, wherein the wash water in the wash tank is not subsequently recirculated through the wash chamber via the wash pump.

13. The method of claim 11, further comprising:

performing a full drain function where the drain ball is opened to drain an entire volume from the wash tank.

14. The method of claim 11, wherein the set volume is approximately 20 percent of capacity of the wash tank.

15. The method of claim 11, wherein the set volume is approximately 30 percent of capacity of the wash tank.

16. The method of claim 11, wherein supplying fresh water dosed with rinse aid and detergent includes dispensing rinse aid and detergent in amounts relating to the set volume of fresh water supplied into the wash tank during the rinse drain function.

17. The method of claim 16, wherein the dispensing is performed using a solid detergent chemistry.

18. The method of claim 16, wherein the dispensing is performed using a liquid detergent chemistry.

19. The method of claim 16, wherein the dispensing is performed using a liquid rinse aid chemistry.

20. The method of claim 16, wherein the dispensing is performed using a solid rinse aid chemistry.