If your dishes are not getting clean even when you rinse them before placing them in the dishwasher, then your water pressure may be too low and unable to remove food streaks or even soap from the dishes. To fix this, you do not need to call a repairman. The pressure switch, which regulates how much nozzle pressure there is coming from the dishwasher jets, can be adjusted with the help of a few household tools, and you will be enjoying sparkling dishes in no time.
How to Adjust the Pressure Switch on Your Dishwasher
Turn off the water and electricity. You can turn off the water by looking under the sink for a spigot handle. Turn it as far to the left as possible, and then test to make sure you have shut the water off by trying to turn on the water in the sink. When you pull the dishwasher out, you will be able to disconnect the electric cord. If you prefer, you can cut the power by throwing the switch to the kitchen in your breaker box. Sometimes, the dishwasher will have its own circuit breaker.
Remove the access panel to your dishwasher. This will be on the back. You will have to pull it out from the wall first to do this.
Find the water heater. It will look like a long tube with a control box attached to it. It would be difficult to miss as the only other items beneath this panel are the pipes and the pump. The pressure switch itself is a round pipe or tube that threads directly into the heater tube itself. The top will be facing you when you have removed the panel.
Remove the cover on the pressure switch. The cover to this switch is a screw-on type that can be unscrewed in a counterclockwise motion by clamping on your locking pliers and turning. The pressure switch adjustment screw will be directly under that cap.
Insert your flat-bladed screwdriver into the adjustment screw. Turning it clockwise reduces the pressure to the dishwasher nozzles; turning it counterclockwise increases the pressure to the nozzles. If you are turning it counterclockwise, be careful not to unscrew it too much, or you may have a leak in the fixture. Try turning it a half turn first and check the pressure by the way everything gets cleaned the next time you run dishes through a cycle.
Reassemble the dishwasher. Once you have adjusted the switch, put the cap back on, screw the access panel back into place and push your dishwasher back into its alcove. Now, you are ready to give your adjusted dishwasher a try.