Anatomy of a washing machine

here from a search engine? click here to go to our main site

What exactly are all those bits in your washing machine?

This page should help you, but first and foremost, make safety your number one concern.

Ensure the machine is unplugged before attempting to remove the lid or back or any screws.

Also remember that a washing machine today is a very complex piece of equipment with high tech digital electronics working next to water carrying pipes and hoses, the two do not mix well. If you are not sure what you are doing, call an engineer.

The pictures that follow are just a general guide, the bits in your machine may appear entirely different. click on the part listed below or just browse down and look at the pictures. (thanks to Europart for the use of their images on this page.)


Its been 10 long years at least since I wrote this and things have moved on, not nessesarily for the better. A lot of Electronics and software are now found in you appliance, replacing many of the components I have mentioned here. A lot of the information here is now obsolete if your machine is less than 8 or so years old. Even us experienced engineers find it hard to understand that certain faults are down to seemingly unrelated components, whats more, the advent of sealed, plastic tubs means many bearing and inner drum changes etc are now not possible.

Due to popular demand, I will leave the repair tips and anatomy on line for those that are interested.



Solenoid valve
carbon brush
pressure switch
Door interlock

Solenoid valve.

This is what lets the water in when required, They can be single (ie one hose in and one out), double (one in two out) triple or even quad. Generally, on most machines, the cold water valve is a double type while the hot water one is single. Washer driers will probably have a triple or more valve as one feed is required for the drier itself.

possible failure symptoms:

machine filling while not in use. Machine not taking in water when required.

back to index

pressure switch.

This is an electrical switch which acts on pressure building up in the narrow pipe that connects to it. They may act on one or more levels and your machine could have more than one of these in it. Sometimes these are built in to the timer/pcb and can only be identified by the presence of the pressure pipe. They are often variable and feed the actual pressure reading to the control pcb rather than in the past when they basicly clicked on and off at set pressure levels.

possible failure symptoms:

Machine overfilling (ie the water not cutting off when the correct level is reached) or the machine not taking in water and attempting to wash with no water present which may lead to other failures such as the heater.

back to index

Heater element.

This sits (usually) in the bottom of the tub and heats the water up to the correct temperature.

possible failure symptoms:

Not heating, blowing fuses.

back to index

Door interlock.

This ensures that the door is locked before the machine can start and safety regulations dictate that the door remains locked until there is no possibility of the drum still turning when the door is opened. This is usually achieved by a thermal type lock which needs to cool down before the door can be released. Some makes use a mechanical type lock that is connected by a cable linkage to the motor and a pecker that reacts in a certain way if the belt is moving and prevents the door from opening.

possible failure symptoms:

Machine dead, not starting, door not releasing, recurring broken door handles, blown fuses.

back to index

Drain pump.

Discharges the water when required to.

possible failure symptoms:

No drain and spin. leaks, noises. (may only be blocked however)

back to index

Carbon brushes.

These fit inside the motor. (there are none on induction type machines) and provide an electrical connection to the revolving part of the motor. They may come in holders as above or loose as below.

possible failure symptoms:

No spin or no wash action (ie drum not turning). Sparking from the motor.

back to index


This is the controller of the machine and tells each part what to do and receives messages from various sensors such as the pressure switch and reacts accordingly. May work in conjunction with the module and may well be replace entirely by the module.

possible failure symptoms:

Programme sticking, not advancing, not heating, no drum action, etc, etc. Sometimes difficult to prove without replacement.

Now days the mechanical progrmme time is pretty much a thing of the past. An electronic control board is fitted to the majority of appliances and may control all fucntions or may work in conjunction with another pcb elswhere in the appliance. Such is the technology that the boards may be supplied as a "blank" ie. with no programme information and the board must then be either programmed to the specific model specifications by fitting a pre programmed eeprom or coded using a pre determined series of button presses to set the specification.

Fault diagnosis may me made easier by fault codes being displayed either by a figure in the led display or by flashing lights.

back to index

Module/ PCB.

This will either control the speed of the motor only or may work in conjunction with the timer and control other aspects such as heating and programme advancing. Some machines may use a module only with no programmer at all.

possible failure symptoms:

No drum action, erratic drum action, spinning when should be washing and, when it controls other functions, heating and programme not advancing faults.

back to index

To top