Common dishwasher faults and problems, what causes them and how to cure them

Common dishwasher faults and how to fix them

If you are trying to rectify any dishwasher faults it is necessary to first identify the source of the trouble. In most instances, troubleshooting a defective dishwasher can prove to be a relatively simple task as long as you are methodical in your approach, and take adequate safety precautions. Identifying the root cause can help you solve most common dishwasher problems at home, and save yourself the costs involved in seeking professional intervention.


My Dishwasher Does Not Start/Power Up

In such a scenario, it is necessary to make sure that the power supply is functioning properly. The first step in solving such a problem is to make sure that your appliance has not been accidentally switched off or unplugged. If this is not the case, you will need to check your main electrical panel for signs that a fuse or circuit breaker has tripped. Ideally, your dishwasher should have an individual circuit breaker that makes it easier to diagnose this type of fault.

In certain cases, the motor appears to be stuck and will not turn; you are left with a low humming sound, but there are no other signs of activity from the washer. This is a common condition when a dishwasher has not been used for a long period of time. Turn off the power at the electrical mains before removing the 2 kick panels under the door. You will need to reach in to gain access to the motor. You can attempt to manually turn the fan blades in order to spin the motor. If these blades do not appear to move, it could indicate a serious problem within the motor. In certain cases the motor spins manually, but will not start when power has been restored to the appliance. This indicates that the motor itself is fine; you could be dealing with faulty wiring, a blocked pump, or even a bad switch.

My Dishwasher Door appears to leak, leaving large pools of water on the floor

There are various reasons for this type of problem to develop, some simple to take care of and others are far more complex. It is therefore necessary to try and pinpoint the underlying cause.

Usually, this type of leak may be traced to a door that fails to shut completely. While you are washing dishes in your appliance you need to check for any leaks that seem to appear directly below the door. If the door appears dry but there is still a puddle of water, you will need to unscrew the 2 front panels under the door and check for leakages that may appear around the hose or any other part. At times, you might be able to secure a hose connection, but these types of leaks are quite complex.

If you do detect signs of water leakages around the door, you can attempt to solve this. Your first step should be to check the rubber seal or gasket for signs of damage. If there are no visible signs of wear and tear, the gasket may simply need to be cleaned in order to remove accumulated grime or food particles. Also make sure to check on the float switch. Lift the float switch cap to ensure that it is not fixed at the lowered position, which can result in tub overfills. Clean out the switch with an old toothbrush and household cleaner. 

Make sure you use detergents that are meant for use with your dishwasher. Using hand washing liquid can result in the overproduction of suds which can then cause leaks. 

You may also need to check your machine door to ensure that it fits snugly. If you can move the door about after it has been closed, you may be required to re-adjust the door. Generally, a dishwasher will have an adjustable latch plate located near the top of the door frame. Making slight adjustments here will help ensure that the door closes tightly, minimizing the possibilities of leaks. However, it is necessary to make sure that you do not over-tighten the door by bending or forcing the latch.

In case of a persistent leak, it could well be that the rubber gasket/seal has been damaged, and will need to be replaced.

My Dishwasher Does Not Clean Efficiently

Poor cleaning might be the outcome of a problem with the spray arms. Check to make sure that the spray arms are able to spin freely. If there are dirt build ups or if the spray arm is stuck, it will have to be removed and cleaned. You can use a pair of needle nose pliers to clean out any debris that could be stuck in the spray arms. You might also need to check the pump intake to make sure that there is no debris blocking it.

It may be necessary to check the float switch to make sure that it is not stuck. The presence of dirt residue can cause it to stay in a raised position that will not allow water to fill within the tub. Water must reach an adequate level above the heating element to ensure that it is properly heated and can deliver a proper cleaning effect to any dishes inside the machine. You can use a small toothbrush or pipe cleaner to remove any dirt that may have accumulated around the float switch. Ideally, the float should be able to move and down without restriction.

Low water levels that lead to ineffective cleaning can also be a symptom of a blocked intake valve screen. The inlet valve is usually located underneath the dishwasher and is accessed from the front. You will need to unscrew the lower front panels and remove the valve before you can reach the screen. Flush out the screen and valve with water to displace any residue that may be trapped here before replacing.

Some Tips for Efficient Cleaning

  • Do not overload the dishwasher 
  • If any items fall under the lower basket, they will stop the spray arm from spinning.
  • Always make sure you are using the recommended detergent for your appliance
  • Scrape away any bits of food from plates before placing them in the washer
  • Use a special rinsing agent/water softening agent if you are using hard water to wash your dishes.
  • Ensure that the water is hot enough by checking the product manual for the ideal water temperature setting.

My Dishwasher is Noisy

Noises from a dishwasher can be a common occurrence when the machine has not been properly maintained. In order to solve this type of problem, it is necessary to understand its underlying causes.

One of the most common causes of a noisy dishwasher is a faulty or blocked drain pump. It may be necessary to clean out the pump or replace it in case of damage.

If your dishwasher emits a continuous droning sound during operation, it could be a sign that there is problem with the circulation pump. A standard problem could be a failure in the pump motor bearings. This issue can only be resolved by replacing the entire pump as this type of damage is usually irresolvable. Such bearing failures are generally seen in the circulation or drain pump motors. 

Loud operating noises may also point to blockages in the drain pump. In order to clean out the pump you will need to remove the outer covering located above the pump housing. 

Alternatively this sound could indicate a failure of the wash or drain impeller, and motor bearings that are essentially a part of the Motor and Pump assembly. While the bearings are irreplaceable, the impellers can be replaced. The wash impeller is essentially the plastic blade that is propelled by the motor. Its primary function is to force water through the spray arms that are responsible for cleaning dishes. If this blade has broken off during use it may cause a loud sound. In case the impeller is bent, it will make contact with the pump housing and create a sound while it is running.

If a dishwasher is unusually noisy while water is being filled, this could point to a defect in the water inlet valve. This is an electronically controlled valve that regulates the flow of water into your machine. As a result of long term degradation the diaphragm within the valve can get misshapen. This results in a vibration or squealing sound during the fill cycle. The water inlet valve can be easily replaced in most cases.

My Dishwasher Will Not Drain Water

Certain dishwasher models utilize a water pump belt, and a loss of the draining capability can indicate that this belt is broken or has been worn out. Accessing this belt is relatively easy. Remove the front panel to gain access to the motor; this belt runs along the underside of the motor.

Usually lack of drainage is indicative of a problem with the drain pump. An Ohm meter can be of help to check if the pump motor is operational or not. If the motor appears to be functioning during the drain cycle, you should inspect the drain line for any solid residue that may be blocking it. A motor that does not run during this cycle is probably damaged. In case of a major defect the drain pump should be replaced. 

Drainage issues can also be linked with worn out or defective drain impellers. The impeller is connected to the drain pump and is responsible for expelling water from your machine into the main drain via the drain tube. If this part requires replacement, it is recommended that you change the drain seal as well.

Damage to the drain solenoid can cause the drain flap to remain closed and prevent water from leaving the machine. If this actuator is defective, it should be changed. 

You should also check the drain valve to ensure that it is free of any solid residue that could be blocking it. If the drain valve does not function after cleaning, it should be changed.

If your dishwasher is connected to the garbage disposal unit, any blockages in the disposer can block the drain. You will need to pull away the drain hose from the disposal unit and check for any sediment build ups at both ends. In case the disposal unit has been recently installed, it could simply mean that the drain plug was not removed from the disposer while it was being fitted. 

A more basic issue for this problem could be a clogged drain hose. This hose can be easily cleaned by removing the connections from the sink drain and the dishwasher.

This type of problem may also be caused when the check valve remains shut. The check valve ensures that there is no back filling of water from the drain into the dishwasher. This valve is located at the end where the drain hose is attached to your appliance, and it can be easily replaced.

My Dishwasher Does Not Dry Dishes Properly

Dishwasher drying issues may be related to defects in the vent damper that is responsible for releasing steam at the end of a cycle. If this vent fails, moist steam circulates within the appliance preventing dishes from drying out.

If your dishwasher utilizes a vent fan to perform its drying function, it may be necessary to check the fan motor for continuity. You may try and spin the fan blades manually to check for any impediments that are restricting its movements.

Most dishwashers have their heating element and assembly placed near the base of the appliance. If this heating element or the assembly is defective or burnt out, your dishwasher will lack the capacity to dry any dishes.

My Dishwasher Does Not Fill with Water

The first step in such situations is to make sure that the dishwasher is properly connected to your home's hot water supply and that the water pressure is sufficient.

Quite often, a defect in the electronically controlled water inlet valve will prevent water from entering the dishwasher. This part cannot be repaired and you will require a replacement. There is also the possibility that the water inlet screen located next to the valve is blocked. This is a common occurrence in areas that depend on hard water. The screen should be removed and cleared of any deposits before replacing it.

Any damage to the float assembly or float switch can restrict the flow of water into the machine. Located at the base of the appliance next to the door, the float assembly should be able to move up or down easily. Designed to prevent the machine from overfilling, this assembly or switch will not allow water to enter the washer if it gets stuck.  

My Dishwasher Lights are Flashing/Blinking

Blinking lights on a dishwasher are generally indicative of a failed machine part. This could indicate a failure of the drain pump, heating element, heating element assembly, control panel or touchpad.  

In most cases, these flashing lights in the display window are accompanied by an error code. These codes provide a clue regarding any defective parts present in the machine.

If you have no experience dealing with common dishwasher faults or are a complete novice when it comes to dealing with electronic appliances, it may be wiser to hire a professional with experience in resolving dishwasher problems.



































Disclaimer: The information provided has been prepared as a guide only and the steps taken are likely to vary for different appliance models. We strongly recommend using a qualified engineer to undertake major repairs and fault finding.


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