HomeIt cleans poorly
If your dishwasher is cleaning poorly, check these:
Most cleaning problems are caused by the dishwasher not getting enough wash water, so the water-inlet valve is often to blame. This valve is usually at the bottom left or right of the dishwasher, behind the lower access panel. It’s the device with the main water line from the house, a rubber tube to the dishwasher, and two wires attached to it.
When a water-inlet valve is defective, you may hear the sound that’s usually referred to as “water hammer.” If the water-inlet valve is defective, you need to completely replace it.
Internal filters
Every dishwasher has some type of filter to keep large food particles and foreign objects away from the pump assembly:
- Most modern dishwashers have self-cleaning filters that don’t need any routine cleaning.
- Some have filters in the bottom of the dishwasher that you need to periodically clean. You don’t need any tools to remove the filter, and cleaning it is easy. Consult your owner’s manual to determine which type you have and its maintenance requirements.
If your filter is clogged, it may be causing the cleaning problem.
Drain valve
Some dishwashers have a valve (or gate) that should open only during draining. If debris lodges in the valve, it can’t close properly, so water drains out during the wash cycle. Most dishwashers drain into the garbage disposer. If yours does that, listen for water flowing into the disposer during the wash cycle. If you can hear it then, the drain valve may be clogged.
Spray arms
There’s a spray arm at the bottom of your dishwasher–it may have a tall spray tube mounted to the center of it. There may also be a spray arm located directly beneath the upper rack of dishes and/or above the upper rack.
If debris is blocking the holes in the spray arms where the water comes out, it could cause cleaning problems. Regularly inspect each of the spray arms and clean out the holes as necessary.
Water temperature
To get the best cleaning results, the water entering your dishwasher needs to be hot enough. Try running the hot water in your kitchen sink for about 30 seconds before starting the dishwasher, to pre-heat it. Also, if your dishwasher lets you select a higher wash or rinse temperature, try that to see if it helps.
To check the temperature of the hot water that comes from your kitchen faucet use a waterproof thermometer. If the water isn’t 120 degrees Fahrenheit, your dishwasher may have trouble getting your dishes clean. You could increase the temperature of the hot water to the whole house–and therefore the dishwasher–by adjusting the hot water heater thermostat.
Warning! To lessen the risk of scalding, don’t set the hot water heater temperature higher than 120 degrees Fahrenheit.
Detergent cup
Dishwashers don’t perform their best if detergent is introduced only at the beginning of a cycle, so add detergent to both parts of the cup.
It’s noisy
If your dishwasher seems noisy, check these:
An aging water-inlet valve can sometimes fail slowly, rather than all at once. It can shudder on and off rapidly, causing the incoming water lines to shake, rumble, and rattle–sometimes violently. If yours is doing this, replace the inlet valve.
Motor
If it’s the motor that’s noisy, either of these may be the “culprit:”
- As motor bearings wear out, they can become quite loud when the motor runs. They wear out quickly if they frequently get wet, because the water washes away the motor bearing grease. Bearings can get wet if the spin seal is defective. Then there will also be water leaking onto the floor beneath the dishwasher. Replace the seal if it leaks (read about the main tub seal in the “It leaks” section, later).
- If, from beneath the dishwasher, you can see a round, plastic disc that’s mounted to the top of the motor (a “slinger”), it may have broken free of the motor shaft. If so, it could be rattling around the shaft while the motor is running. If that’s the problem, you need to replace the motor.
Heater fan
If the heater fan bearings are rusted or worn, they may squeal, or scrape loudly during the drying cycle. If this is the problem, replace the fan motor. Alternatively, the fan blade may be loose. If so, you need to replace it.
Pump
Small fruit pits, toothpicks, and fragments of glass sometimes get stuck in the pump. When this happens, open the pump and remove the debris. The pump is usually mounted directly to the motor, then attached to the bottom of the dishwasher.
To get to the pump, you usually need to remove the lower rack, the spray arms, and the spray arm support from the inside of your dishwasher. A dishwasher pump isn’t obvious. Look for an impeller–a round, plastic fan blade-type device that spins around and pushes the water toward the drain. When you can see the drain impeller, you should be able to see the clogging debris.
It leaks
If your dishwasher leaks, check these:
Note… If the main motor of your dishwasher is mounted vertically, beneath the center bottom of the dishwasher, the following instructions probably apply to you. But if your motor is mounted horizontally, the pump isn’t serviceable–you need to replace the entire pump and motor assembly.
The main tub seal is beneath the drain impeller. It prevents the water in the dishwasher from leaking out near the shaft of the motor. To get to the seal, which is inside the dishwasher, remove the:
- Lower rack
- Spray arm
- Spray arm support
- Wash/drain impellers
Then pry the seal out of its housing and replace it.
Door gasket or seal
Over time, door gaskets and seals harden and lose their ability to seal properly. You can’t repair the seals. You need to replace them if they’ve begun to leak.
Water-inlet valve
The water-inlet valve, itself, seldom leaks. But, the water-supply line from the house and the rubber tube leading from the valve to the inside of the dishwasher may leak. Tighten or repair/replace these as necessary.
The water-inlet valve could mechanically stick open. When that happens, the water continues to flow into the dishwasher, which then floods your kitchen. Turn off the water supply to the dishwasher, and replace the valve.
Hoses
Behind the lower access panel on your dishwasher are several rubber or plastic hoses. If the leak appears at a connection, try a new clamp. If that doesn’t work, replace the hose.
