The dishwasher is buzzing

Many dishwasher issues are easy to fix yourself. Even if there is a major defect, it helps to isolate the damage to keep subsequent service costs low. A malfunction that can have many causes is when the dishwasher is buzzing.

The functioning of dishwashers

In order to be able to better allocate a source of error, it is necessary to know the mode of operation of a dishwasher better. Before that you should at least know the basic components:

  • Solenoid valve for the water inlet
  • Lye pump for pumping out the dirty water
  • Circulation pump to use the maximum flushing water
  • Instantaneous water heater or heating coil for older appliances
  • Ion exchanger as a water softening system
  • lateral water splashes to cool the inner walls (so that water vapor can condense when drying)
  • various sensors and associated magnetic switches or solenoid valves
  • Program control including board and various relays

To the program start

In the dishwasher there is still water in the so-called pump sump. This residual water is pumped out on most devices when restarting the program, before fresh water enters. Here, the drain pump, solenoid valve for the water inlet and possibly sensors with corresponding magnetic switches play a role.

Cleaning, rinsing and drying

The circulation pump, on the other hand, only moves the water for cleaning and rinsing, but does not pump it out of the machine. The drain pump is responsible for this. For new devices that have side water pockets for cooling, these must also be filled via magnetic switches or valves. This process starts immediately before drying. The program cycle of the dishwasher can therefore be subdivided into different areas:

  • the pumping out before the program starts
  • the water inlet before rinsing
  • circulating the water through the circulation pump
  • draining the cleaning water
  • the admission of the rinse water
  • the pumping out of the rinse water
  • the filling of the water bags

Everywhere the hum can be triggered

All these tasks take place at different times during program execution. The hum of the dishwasher can therefore be roughly assigned to the date already over. The only question now is whether the hum is triggered by a relay, a solenoid valve or a pump.

Locate and determine program time

In turn, it helps to locate the sound. On the basis of an exploded view of the device, these areas of the dishwasher can be better assigned in the absence of specialist knowledge. If there is a fault with relays or a solenoid valve, well-grounded electrical knowledge is required in any case. In modern machines, the fault memory must also be identified via the corresponding interface.

Simple sources of error

However, there are causes that are relatively easy to fix. If it is suggested that the noise comes from a pump, it may either be clogged or there may be a foreign matter in the impeller housing. Take the sieves out of the dishwasher. For most devices, you can access the impeller housing via the pump sump or at least its inlet. For other devices, it is slightly laterally.

The water inlet

But you can at least check if the sieve is clogged or there are foreign bodies in the pump sump. If the buzzing hangs together with the water inlet, the dishwasher may not draw water. Here, above all, the inlet area comes into question. So the following parts:

  • Shut-off valve (water connection)
  • the next sieve
  • the following aquastop box
  • a kink in the inlet hose
  • the solenoid valve for the inlet

The valve can hum, because it does not open, but also when there is no water and it is powered by external voltage. In this case, electrician knowledge is needed again.

Tips & Tricks

So you see, the only reason is that it's hard to categorize it by humming on its own. However, if you can describe the function that has failed, it becomes much easier to assign that hum. It may occur when the dishwasher is not heating, the dishwasher is not pulling water or there is water in the dishwasher. The house journal offers you numerous advices and articles for the dishwasher. All errors are described exactly. So you should be able to assign the hum.

Video Board: Dishwasher Motor Buzzing? Fix it in one minute.