Dishwasher Basics - How They Work


The motor and pump system

Your dishwasher has at least one motor. It is attached to a pump, which forces the water up into the sprayer arms. During the drain cycle, it also pushes the water out of the dishwasher…down the drain. A few European dishwashers use two separate motors, one for spraying and one for draining.

The controls, switches, valves, and solenoids

A dishwasher has at least three, but often six or more controls, switches, valves and solenoids. Timers, selector switches, water-inlet valves, float switches, soap and/or dispensers, drain solenoids, thermostats, soil sensors, door switch, drying fan, and the heating element are all potential types of items that fall in this category. You can find more details about each of these types controls at's site.

The interior

The dishwasher interior contains the dish racks, the spray arms, and/or the tower that sprays water at the dishes, the upper part of the pump assembly, and the water filter.


A dishwasher works similar to a robot going through cycles after we load in our dishes. The timers and controls are like self-monitoring systems to make sure the cycle runs smooth:

  1. Fills itself with water
  2. Heats the water to the appropriate temperature
  3. Automatically opens the detergent dispenser at the right time
  4. Shoots the water through jets to get the dishes clean
  5. Drains the dirty water
  6. Sprays more water on the dishes to rinse them
  7. Drains itself again
  8. Heats the air to dry the dishes off, if the user has selected that setting
Parts, Videos, Help, at