Washing machine repairs - theory

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A description of the typical faults and failures found in domestic washing machines, and guidance on fixing them.

This introductory text to Washing Machine repair assumes reasonable DIY, mechanical and electrical competence. It does not attempt to explain how to open up the machine to access the innards, because they are virtually all different in how they come apart. It is hoped to add a generic guide later, covering this.

The Haynes “The Washing Machine Manual” by Graham Dixon, ISBN 0854296905, gives more detailed advice than we have room for here, together with photos that show you what to expect.

For more specific help try posting a question to either the uk.d-i-y newsgroup or to the appliance-repair Yahoo! group.

Before you start

The first thing to do is pull the machine out for access and unplug it. Often the machine is plugged into a socket that's inaccessible until the machine is pulled forward (see #accessible_socket" how it should be done below). Do not open the appliance, or fault-find internal parts while the power is connected.

If you need to move the washer, watch you don't put undue stress on the water hose(s), water at mains pressure has a curious knack of getting everywhere you don't want it to go. Turn off the water isolation valve(s) on the wall. If disconnecting the hoses, place the open ends in a container to collect the water they contain. Once most water is drained, a plastic bag over the open end held in place with an elastic band will collect most remaining dribbles.

Faults

Why won't my washer do anything at all?

A fault on a dead washer is actually quite easy to trace.

  1. First eliminate the fuse in the plug, or a faulty mains socket.
  2. Next check the door switch and the wires leading to it.
  3. Then check for a faulty on/off switch or loose or disconnected spade connectors (a visual inspection)
  4. Check mains power is getting out of the electrical filter on the mains input. This is a large-ish can.

My washer is leaking, why?

There are several reasons for a washer leaking, it could be a broken door seal, pump or pipe. These require a visual inspection of where the leak is coming from, and either a cleanup and refit or sometimes replacement of the offending part.

A tell tale signs of a pump leaking is a white residue around the pump mountings where soapy water has evaporated and left a trail of dried soap.

The door seal performs two functions, its stops water from getting out through the hole where the clothes are placed into the drum, and it also bridges the gap between the front of the cabinet and the wash tub. A leak in the door seal might drip water just behind the front face of the machine, and this is usually caused by a hole in the seal which must be replaced. A leak down the front panel could be caused by an ineffective seal between the rubber and the door glass, which might be solved by simply cleaning any soap residue away from the glass, and a smear of washing up liquid around the edge of the door seal might be enough to restore a good seal. Should this not work then a replacement seal would be necessary.

The seals are universal in their fitting methods and require removing from the front panel first, then access can be made to where the door seal fits to the tub.

Another cause of a leak is overfilling, which can be caused by the water level sensor being faulty. This consists of a pressure barrel which can be located at the bottom of the tub on the back, or on one of the pipes leading to the pump. It forces air up a pipe as the water level is increased. The pipe leads to a pressure chamber which activates the water level switch, or switches, depending on how many levels of water are detected by your model of washing machine. Common failure points here are a blocked pressure chamber (soap residue), a split pipe, detached pipe or broken pressure switch. The pressure switch (Pressostat) can be tested by removing the pipe and blowing into it, you should hear distinct clicks for each water level.

Why won't my washer spin?

There are several reasons for this fault. First it won't spin if there is water in the tub. If this is the case, then check “Why won't my washer empty?”. Even though the washer might have emptied the water, the machine might be misled into thinking there is still water left in the machine due to a blocked pressure barrel (see “My washer is leaking, why?”). If the belt has become detached or loose, the drum will not spin, nor will it spin if you have a faulty motor, module or timer. Usually a motor will have carbon brushes which slowly wear away. There needs to be enough material left to touch the commutator and have enough spring left in them to make sure there is a good contact. If the brushes in the motor are OK then you need to check the circuit across the terminals on the motor, because there is a thermal overload switch inside which may have tripped. Should the motor be OK, or be the type that doesn't have brushes (induction), then the chances are you need to test the speed control module. This is a circuit board that directly controls the speed of the motor. It may be found on or near the timer, or sometimes at the base of the machine, and usually requires specialist equipment to determine its worthiness.

Why won't my washer empty?

Before examining the fault, it is usually worth trying to empty the machine manually, this can be done by removing the outlet pipe and lowering it into a bucket, when gravity should allow the water to empty from the machine. This doesn't work with certain German made machines where the mounting for the outlet hose is too high to allow a gravity discharge.

Often the reason for non-emptying is a blockage. This usually involves removing the pipe connecting the bottom of the tub to the pump, but dirty water will gush out. The blockage could be due to a lost item of underwear or a broken-up soap ball. The soap ball is a supposed to make the machine more efficient by keeping the soap in the tub, but it frequently jams and causes machine emptying problems. If there is no obvious blockage then you need to check the pump, which you can do by putting the machine on an empty cycle and listening to see if the pump is turning. However, even if the pump is rotating it is possible that the rotor has come loose or has broken vanes, so you really need to check that it can generate water flow. If the pump is not turning then check for an obstruction directly in the pump, such as a coin or bra-wire. If the pump is working fine, then the trickiest problem of all could be a coin in the outlet pipe. This is a hard one to diagnose because this kind of item is very difficult to find. The best cure for this is to have a pole which is close to the internal diameter of the pipe and shove it from one end to another.

Why is my washer banging?

A banging washer can be caused by an unbalanced load, caused by an overloaded machine or an underloaded machine. If the machine is constantly banging then one of the following may be the cause.

An unregulated motor

The module that controls the motor needs adjusting or replacing or the motor needs calibrating, because the speed is finely regulated to balance the wash load when the machine goes into spin. After the machine has tumbled it goes into distribution mode, and this is where most of the problems occur. The drum has to build its speed from tumble (35-55 rpm) to distribution speed (83 rpm). If this does not happen gradually, the clothes gather at one side of the drum and create an out of balance load. Hotpoint and Servis (older carbon brush) motors can be adjusted by turning the brass calibrating ring on the tacho assembly attached to the back of the motor. Otherwise you need to take the control board to be repaired, re-calibrated or replaced.

Faulty suspension

There are two common types of suspension, a spring and friction plate type and a shock absorber type. The first one suffers from the friction plates becoming shiny and not gripping properly. This can be cured by either replacing the friction pads, or simply sanding down the surfaces of the pads to roughen them.

The shock absorber type can suffer from broken legs, or loss of oil in the dampers. Either case would cause the tub of the washer to be loose and free to move around inside the cabinet.

Loose components

Any component from the motor to the concrete block at the top or bottom of the machine can become loose and cause banging. This requires visual inspection and repair.

Drum Bearings

Bearing faults are usually indicated by a rumbling sound which gets louder with time.

Replacing drum bearings is quite doable and not expensive, but a pain of a job with a fair bit of disassembly. Details vary from machine to machine.

Broken spider

The drum is supported on a 3 legged casting, the 'spider'. If a leg breaks, spinning without severe banging is impossible. A broken spider is easily spotted: the drum can be moved sideways relative to the tub in one direction, but not at 90 degrees from it - ie it freely moves up & down but not sideways, or vice versa.

Motor bearings

Motor bearing faults are quite rare, but can be identified by removing the belt and manually turning the motor. Faulty bearings will make the motor harder to turn or noisy when it is turned. Usually this is caused by over tightening the belt, and the cure depends on which make of machine. Some machines have replaceable bearings, some need the armature replacing, and a few need to have the motor replaced as a whole unit.

Why is my washer sticking mid-cycle?

The washer can stick mid-cycle because the timer is usually waiting for a condition, such as the water filling up to the level, or the water heating to the correct temperature. These are fairly obvious to resolve, by either replacing the water valve or heater element. However, there is one fault which is tricky to resolve and that is the siphoning effect. This happens when the drain hose gets pushed too far down the standpipe and the water siphons out as fast as it is taken in, hence it never gets filled up, so the timer continually waits.

Why won't my washer door open?

The most common type of door interlock is a thermal delay lock, which is why some machines take time for the door to release. So make sure you have waited a minimum of 2 minutes before you open these or conclude that they are faulty. This type of interlock cannot be repaired and quite simply have to be broken loose from behind the front cabinet, and replaced. With the power isolated you need to remove the top cover and put your hand down behind the front panel to where the door lock is located (directly behind the hole where the door catch enters the cabinet). The door catch then has to be prised away from the front of the cabinet until the door opens or the interlock breaks.

Some machines will not let you open the door if the machine has water in it, or the drum is turning, so first make sure the water has been emptied from the drum, then check the mechanism which detects the motion of the drum. This motion detector can be attached to the motor or the drum pulley, and is a mechanically operated lever attached to the door lock by a cable.

If there is resistance to the cable being shortened then the door will open, however if the cable offers no resistance the door will not open. The mechanism on the motor or drum pulley consist of a lever with a pecker assembly at the end. The lever is pulled towards the belt when you try to open the door. The pecker at the end of the lever is at right angles to the belt and is what provides the resistance to the cable, but if the belt is moving the pecker gets pushed to one side and the cable has a fuller range of movement, hence offers no resistance for the door to open. Sometimes the pecker assembly can break and needs to be replaced, otherwise it is just a matter of adjusting so there is a miniscule gap between it and the belt.

Why is there always softener left in the tray when the programme has finished?

The softener is emptied using a built-in siphon, water is sprayed into the softener compartment and it siphons out through a tube in the middle of the tray. The syphon pipe is easily blocked and needs to be cleaned out. A pipe cleaner works fairly well.

It stopped with water still in it, and I opened the door!! I should not have been able to do that, should I?

Unfortunately with some machines it is quite possible to open the door with water still above the door line, because they rely on a time delay only, whereas others actually check that the water has been drained. See “Why won't my washer door open”.

Clothes come out dripping wet

This happens when the machine refuses to spin. By far the most common cause is overloading the machine.

There is a workaround that works with some machines: set it to spin on the lowest spin speed. When this is done, often it'll then spin at high speed.

If it won't do that, spin dry the load in 2 batches.

For more info, see 'Why won't my washer spin?'

Smells

See Washing Machine Smells

I want to put in a socket for my machine, any hints?

The usual method is to put a socket on the wall under the worktop in the machine space. This has two disadvantages:

  1. It obstructs the machine so it cannot be pushed fully against the wall, causing it in some cases to protrude beyond the worktop. If in a corner situation this can prevent adjacent drawers or doors from being opened.
  2. The machine cannot be electrically isolated except by turning off the mains at the consumer unit. This is at best an inconvenience and at worst a danger should a serious fault, like a flood or fire, develop.

The other way to do it is to fit the socket outlet to the left or right of the under-worktop space, in the dead space behind an adjacent floor unit. You will need to cut an access hole in the rear of the adjacent unit's side panel, large enough to reach a hand through, holding a 13A plug. A 3" or 4" square hole should do it.

Ideally a separate isolation switch should be fitted above the worktop in a convenient position, and an unswitched socket used.


See also