How It Works
Most dishwashers use sliding
racks to hold your dishes while spray nozzles on rotating arms shoot powerful
streams of hot water to get your dishes clean. The arms rotate with a connected
drive motor and may move up and down to reach every tray. A heating element
mounted on the lower portion of the bottom rack provides heat during the drying
cycle, and many units are equipped with water heaters to increase the
temperature of the wash water. Dishwasher Detergent
is automatically released during the wash cycle. Controls are usually located
on the front of the dishwasher.
What Can Go Wrong?
The most common issue with older units is deterioration of the bottom seal which results in leakage. Cost to replace a bottom seal may approach costs to replace the entire dishwasher. Many modern dishwashers have controls embedded in a circuit board. If these controls fail, they are not repairable and must be replaced as a unit.
Automatic valves control the ratio of hot and cold water based on cycle settings. If these valves fail, the dishwasher will be unable to operate during the wash cycle. Motor breakdown sometimes makes the dishwasher inoperable. When possible, replacing a broken motor usually requires a complete removal of the dishwasher from its location.
Environmental Impact
Consider the cycle settings you typically use: heating
cycles have the largest impact on energy efficiency
and cost. A typical dishwasher (1200 watts) might use 30 kilowatt-hours (kWh)
of electricity per year (at 30 loads per month), while producing about 46
pounds of carbon dioxide (CO2). This excludes energy consumption and CO2 production from
the home water heater that heats the water used by the dishwasher.