LG QuadWash Dishwasher: Troubleshooting Spray Arm Nozzle... | appliancefaults.com

Technical Background:

The LG QuadWash utilizes an MCU to control the various components of the dishwasher. The MCU sends signals to the water inlet valve, circulation pump, and diverter valve (if equipped). Voltage paths supply 120V AC to these components based on the wash cycle selected. Feedback from sensors, such as the water level sensor, is used to adjust the wash cycle parameters.

Symptoms:

The homeowner reports that the dishes, especially those on the top rack, are not getting clean. They've noticed the spray arms are not spraying with the same force as before, and there seems to be less water reaching the upper racks.

Possible Causes:

Clogged spray arm nozzles due to hard water deposits or food particles.
Low water inlet pressure to the dishwasher.
Faulty circulation pump not providing adequate pressure.
Partially blocked filter(s) in the dishwasher tub.
Defective diverter valve not directing water properly to all spray arms.
Air lock in the pump or water lines.

Solution:

1

Unplug the dishwasher or turn off the breaker at the breaker panel.
2

Remove the spray arms and clean each nozzle with a small brush or toothpick to remove any blockages. Rinse thoroughly with warm water.
3

Check the water inlet valve for proper function. Use a multimeter to verify 120V AC power to the valve when the dishwasher is calling for water. Replace if defective.
4

Inspect and clean the filter located at the bottom of the dishwasher tub. Remove any debris or buildup.
5

Examine the circulation pump for obstructions or damage. Check the impeller for free rotation. If the pump is noisy or not functioning, replace it.
6

If the dishwasher has a diverter valve, check its operation. Use a multimeter to test the valve solenoid. Replace if the solenoid is open or shorted.
7

Check the water supply line to the dishwasher for kinks or restrictions. Ensure the water pressure is within the manufacturer's specifications (typically 20-120 PSI).

Safety Warning:

Always disconnect power to the dishwasher before performing any repairs. Use proper Lock-Out/Tag-Out (LOTO) procedures to prevent accidental energization. Be aware of high voltage (120V AC) when working on electrical components.

Prevention:

Regularly clean the dishwasher filter and spray arms to prevent clogging. Use a dishwasher cleaner monthly to remove mineral deposits. Consider installing a water softener if you have hard water.

Expert Tip:

To enter service mode on some LG QuadWash models, press and hold the 'Rinse' and 'High Temp' buttons simultaneously for 5 seconds. This will allow you to run diagnostic tests and check component functionality.

Frequently Asked Questions

•How do I check the water inlet pressure to my dishwasher?

You can use a pressure gauge connected to the water supply line with the dishwasher disconnected. A reading between 20-120 PSI is usually required.

•What is the typical lifespan of a dishwasher circulation pump?

A dishwasher circulation pump typically lasts between 7-10 years, depending on usage and water quality. Hard water can shorten its lifespan.

•How do I know if my diverter valve is working correctly?

Observe the spray arm action during different wash cycles. If water isn't being directed to all spray arms at some point, the diverter valve might be faulty. Listen for unusual noises from the valve during operation.

LG QuadWash Dishwasher: Troubleshooting Spray Arm Nozzle Pressure

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•How do I check the water inlet pressure to my dishwasher?

•What is the typical lifespan of a dishwasher circulation pump?

•How do I know if my diverter valve is working correctly?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: