The document explains the function and history of dishwashers, detailing their evolution from early designs to modern built-in, portable, countertop, and drawer types. It describes the mechanism by which dishwashers operate, including water supply and circulation during cleaning cycles. Additionally, it outlines the advantages and disadvantages of using dishwashers, emphasizing water and time efficiency alongside potential costs and maintenance issues.

1. DISHWASHER
Mrs.R.Chitra, AP(SS)/ECE, School of
Engineering, Avinashilingam Institute,
Coimbatore

2. INTRODUCTION
• A dishwasher is a machine that is used to clean dishware, cookware, and cutlery automatically.
Unlike manual dishwashing, which relies heavily on physical scrubbing to remove soiling, the
mechanical dishwasher cleans by spraying hot water, typically between 45 and 75 °C (110 and 170
°F), at the dishes, with lower temperatures of water used for delicate items.
• A mix of water and dishwasher detergent is pumped to one or more rotating sprayers, cleaning the
dishes with the cleaning mixture. The mixture is recirculated to save water and energy.
• In addition to domestic units, industrial dishwashers are available for use in commercial
establishments such as hotels and restaurants, where many dishes must be cleaned.
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3. HISTORY
• The first mechanical dishwashing device was registered in 1850 in the United States by Joel
Houghton. This device was made of wood and was cranked by hand while water sprayed onto the
dishes. This device was both slow and unreliable. Another patent granted to L.A. Alexander in
1865 was similar to the first but featured a hand-cranked rack system. Neither was practical or widely
accepted.
• Initially, dishwashers were sold as standalone or portable devices, but with the development of the
wall-to-wall countertop and standardized height cabinets, dishwashers began to be marketed with
standardized sizes and shape integrated underneath the kitchen countertop as a modular unit with
other kitchen appliances.
• By the 1970s, dishwashers had become commonplace in domestic residences in North America and
Western Europe. By 2012, over 75 percent of homes in the United States and Germany had
dishwashers.
• In the late 1990s, manufacturers began offering various new energy conservation features in
dishwashers. One feature was the use of “soil sensors,” a computerized tool in the dishwasher which
measured food particles coming from dishes. When the dishwasher had cleaned the dishes to the point
of not releasing more food particles, then the soil sensor would report the dishes being cleaned.
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4. TYPES OF DISHWASHER
BUILT IN DISHWASHER:
Built-in dishwashers are the most popular and recognizable types of dishwashers. A built-in
model has an independent and permanent connection to your plumbing, unlike some dishwasher types
that need to route water from your sink plumbing.
The sides of a built-in dishwasher are unfinished, so you can remove it easily after
disconnecting the plumbing and unscrewing two connection points at the front of the dishwasher.
PORTABLE DISHWASHER:
Portable dishwashers are compact, freestanding units that connect to your sink instead of
having its own plumbing. As long as you have an adapter for your sink faucet, this appliance can be
connected directly to your kitchen sink whenever you need to wash dishes, then disconnected and put
away for storage afterward. The top of the dishwasher is usually a countertop material, giving you extra
working space if needed. This type of dishwasher is popular for small homes and apartments and for
those who move frequently but want to take their dishwasher with them.
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5. TYPES OF DISHWASHER
COUNTER TOP DISHWASHER:
When even portable dishwashers are too inconvenient for your space, you can choose a
countertop dishwasher instead. Countertop dishwashers are versatile, easy to use and small enough to sit
on your counter. They connect to your sink using a quick connect adapter and use less water and
detergent than standard dishwashers. However, countertop dishwashers have a lower capacity than other
types of dishwashers, so they are a better option for small households than large households.
DRAWER DISHWASHER:
Drawer dishwashers have two levels that open like drawers rather than having a pull-down
door. These dishwasher drawers are designed to be loaded and unloaded conveniently from the top and
reduce strain on the body from bending. If dishwasher accessibility is a concern, this may be the best
dishwasher for you.
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6. BUILT IN DISHWASHER
PORTABLE DISHWASHER COUNTER TOP DISHWASHER DRAWER DISHWASHER

7. WORKING PRINCIPLE OF DISHWSHER
• In order to wash the dishes, the dish washer tub must contain water .
• The water supply valves in home opens and supplies water to the dishwasher.
• Then the water runs through the solenoid valve ( solenoid is a electrical control valve it provides an
electrical signal regulating the water flow in the circuit ).
• Then it flow through the water distributer, which divides the water flow to one side for washing and
to another for regenerating.
• Then the water flows towards water compartment and the resin dishwasher, alt regenerates the resin
when they are saturated with calcium deposits the resin have the ability to retain calcium for water
softening before washing.
• Now the water is ready to fill the tub, then runs through the circulating pump which pumps the water
to the heating element that will heat up the water before reaches the spray arm
• During the wash cycle ,the water in the tub run in the closed circuit between the tub, circulating
pump, the heating element and the spray arm.
• Once the wash cycle is complete ,the water is drained by the drain pump which is directly connected
to the sewer system.
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9. ADVANTAGES OF DISHWASHER
• Uses less water
• Saves time
• Eliminate germs
• Regulate amount of water and electricity
• According to amount dirt, the temperature can be switched
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DISADVANTAGES OF DISHWASHER
• Significant costs
• Lead to water damage
• Getting lazy
• Cannot decide detergents
• Repair and maintanace is to be regular

10. APPLICTION OF DISHWASHER
• Cleans tough stains and hard-to-reach areas
• Less Housework
• More hygienic
• Saves Water
• Time efficient
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11. THANK
YOU