How a front-loader washes clothes

Q: Washer: one cause of “Won't drain”

Cause: Coins and hairpins are clogging the drain filter, so the water can't reach the drain pump. What you see: The drain pump runs with a “humming” noise, but not a drop of water leaves the outer tub. After a while the machine stops. What the technician does: The technician first lets the water out of the tub, opens the filter flap, unscrews the drain filter, clears out the debris and fits it back.

Q: Washer: one cause of “Drum won't turn” — Belt came off

Cause: The drive belt has fallen off into the bottom of the machine, so the motor's turning force can't get to the drum pulley. What you see: The water is in and the motor still turns, but the drum doesn't move at all. Turned by hand, the drum spins like a windmill, with no resistance. What the technician does: The technician takes off the back panel and loops a new drive belt over the motor pulley and the drum pulley (the old belt goes back on only if no suitable belt is available and the old one is undamaged).

Q: Washer: one cause of “Drum won't turn” — Worn brushes

Cause: The motor carbon brushes have worn short. They no longer press firmly on the commutator, so the motor doesn't get enough current. What you see: The water is in, and the motor twitches and sparks, but the drum just won't get going. What the technician does: The technician takes out the carbon brushes on both sides of the motor and fits a new pair.

Q: Washer: one cause of “Shaking badly”

Cause: The felt friction pads in the shock absorbers have worn away, so nothing soaks up the swinging of the outer tub. What you see: As the spin speeds up through the resonance zone, the outer tub swings hard and knocks the cabinet, and the whole machine jumps. What the technician does: The technician first rules out uneven feet, confirms the shock absorbers have failed with the “basketball test”, then replaces the whole set.

Q: Washer: one cause of “Won't fill”

Cause: The filter screen in the inlet of the water inlet valve is clogged with sand and rust. What you see: The tap is on and the water inlet valve is open too, but the water only dribbles in, and it takes ages to reach the water level. What the technician does: The technician takes off the inlet hose, pulls the filter screen out of the water inlet valve with long-nose pliers and cleans it.

Q: Washer: one cause of “Door leaking”

Cause: There's a hole in the bottom of the door seal, so it leaks once the water rises above it. What you see: During the wash, water drips from the door at the 6 o'clock position and pools on the floor. What the technician does: The technician fits a new door seal.

From the outside it's just a drum that turns. Inside, plumbing, a motor, suspension and a programmed control board work together to shake the dirt out. Drag the view to turn it, take it apart chapter by chapter below, and finally simulate the faults technicians meet most often.

This page is the text version of the 3D lesson. The sliders, buttons, simulations, charts, moving dots, cutaway views and what the text says is showing “now” are all in the 3D lesson. Open the 3D lesson

1. Two tubs, one stays still

The outer one, with no holes, is the outer tub. It holds the water, hangs from the suspension springs (also called hanging springs), rests on the shock absorbers below and doesn't turn. Inside it, the stainless-steel drum, with small holes and a pressed pattern, is what turns; the clothes go in here. The water in the outer tub soaks the clothes through the drum's holes. At the front, the door seal seals the tub mouth to the cabinet and flexes as the tub swings.

Go deeper: Two tubs, one stays still

The drum is held up as a “cantilever” on a single drum shaft at the back of the machine. The shaft runs through the drum bearings at the back of the outer tub, usually two ball bearings. The one nearer the drum takes the most force, so it is usually the bigger one. On the back of the drum, an aluminium-alloy three-arm bracket, the drum spider, locks the drum firmly onto the shaft. How hard do the bearings work? With just 0.2 kg of clothes off to one side, at 1400 rpm and a radius of 0.245 m, there is a rotating force of F = mω²r ≈ 1000 N. That is about the weight of 100 kg, and it swings round 23 times a second.

In front of the bearings sits a shaft seal (lip seal): a rubber lip ring presses on the shaft to keep water out. Over time the lip wears. Wash water and detergent then seep into the bearings and wash the grease away, and the steel balls and races start to rust and pit. It typically goes like this: first a “rumble” during the spin, louder the faster it turns; then, as it gets worse, the drum becomes clearly loose and even rubs against the outer tub. After years of soaking in detergent water, the spider can also corrode and crack, so the drum wobbles. That is a common cause of “Broken drum shaft”, but not the only one: a failed shaft or bearings can cause it too. Fixes doesn't repair a broken drum shaft and recommends replacing the machine.

How to check: switch off the power, open the door, hold the front edge of the drum and rock it up and down. Normally there should be almost no play. Turn it slowly by hand and listen for a “gritty grinding” sound. Brown rust streaks near the bearings at the back of the outer tub most often mean the shaft seal has leaked. The bearings and the shaft seal are replaced as a set. On many newer models the outer tub is two halves welded together, so replacing the bearings may mean replacing the whole outer tub [varies by model]. Fixes generally doesn't replace bearings and usually advises the customer not to repair them. Fixes doesn't send machines back to the manufacturer for repair either. The gap between the drum and the outer tub is only a few centimetres. Bra underwire or coins that fall in can scratch the drum, pierce the outer tub or jam the heating element.

2. Filling: water flushes through the detergent drawer

Press start and the door lock (interlock) first locks the door hook: a lock pin inside slides out and catches it. Only then does the control board (PCB) open the water inlet valve at the back. Tap water flushes through the detergent drawer, picks up the detergent and runs down the detergent hose (dispenser hose) into the outer tub. The water level sensor (pressure switch) measures the level: the deeper the water, the higher the air pressure in its hose, so the board knows when to switch the inlet valve off. Drag the “Load” slider: on many models, more clothes means more water.

Go deeper: Filling: water flushes through the detergent drawer

The water inlet valve is a pilot-operated solenoid valve. Powering the coil only lifts a small plunger, which opens a small bleed hole; what actually pushes the big diaphragm open is the water pressure itself. So the valve needs a minimum water pressure to open properly [check the model's manual for the minimum; to be confirmed]. Water pressure depends on height: about 1 bar for every 10 m of water. If the home is fed by gravity from a rooftop tank and sits high up, only one or two floors below the tank, the pressure may be only a few tenths of a bar. The machine then fills very slowly, or even shows a fill timeout error. On a 220 V valve the coil resistance is about 3⁠–⁠5 kΩ; if it reads open circuit, the coil is broken. AC 220 V and DC 12 V inlet valves are not interchangeable.

The water level sensor (pressure switch) works on hydrostatic pressure: p = ρgh, about 1 kPa (10 mbar) for every 10 cm of water depth. At the bottom of the outer tub is an air trap. As the water rises, it compresses the air inside, which pushes on the diaphragm in the sensor through the water level sensor hose. In a mechanical sensor the diaphragm presses against a spring, and at the set pressure it switches its contacts with a “click”. There are usually several sets: empty, wash level and overflow level. An electronic sensor turns the pressure into a frequency signal, and the control board (PCB) works out the water level.

A common trap is siphoning. If the drain hose hangs too low, with its outlet lower than the water in the tub, or is pushed in too deep and sealed tight into the floor drain, the water flows away by itself as it comes in. The machine keeps filling, shows an error and wastes water. The highest point of the drain hose usually needs to be about 60⁠–⁠100 cm above the floor [check the model's manual]. The vent hose (air hose) isn't there to break a siphon: it lets air pass between the detergent drawer and the outer tub. If it clogs, water runs down out of the drawer slowly, or the drawer even leaks. Also, if the air trap is dirty, or the hose is kinked or has water in it, the water level sensor reads wrong. It may overfill until water reaches the door, or think there is no water at all. You can pull off the hose and blow gently into the sensor, listening for a “click”. Don't blow hard: it will damage the diaphragm.

3. Washing: tumbling, not stirring

During the wash the drum turns slowly, only about 50 rpm, alternating forward and reverse. The three drum paddles on the drum wall lift the clothes, which fall back into the water, thumping down again and again. If the drum turns too fast, the clothes stick to the wall and stop falling; this critical speed is about 60 rpm. Turn on “Slow motion” to see it more clearly.

Go deeper: Washing: tumbling, not stirring

You can work out the critical speed yourself. For the clothes to stay pressed against the drum wall without falling, the centrifugal acceleration ω²r must be at least g. So n_c = (30/π)·√(g/r) ≈ 29.9/√r (r in metres). With r = 0.245 m, that is about 60 rpm. Washing uses about 50 rpm, 80-odd per cent of the critical speed. The clothes rise to about 45° above the horizontal before they leave the drum wall (sin α = (n/n_c)²). The drum paddles carry them a little higher, then they drop 30⁠–⁠40 cm.

How clean the wash gets depends on the four parts of Sinner's circle: chemistry (the detergent), temperature, mechanical action and time. Take one away and the others have to make up for it. That is why a low-temperature eco programme is usually especially long: it trades time for temperature. When a customer says “the eco programme takes ages”, it is most often working as designed, not a fault.

Mechanical action needs “room to fall”. If the clothes are packed in too tightly, they have no space to rise and fall, so they just soak: they don't get clean and they wrinkle easily. Too much foam also turns into a “cushion” that soaks up the force of the drops. A front-loader uses little water, so it must use low-suds detergent. Lots of foam may also make the water level sensor (pressure switch) read high and put more load on the motor. The machine then automatically adds water for an extra rinse, or pauses [varies by model]. When a customer complains the wash isn't clean, first ask how much they load and which detergent they use, then check the machine.

4. Heating: the element sits in the bottom of the tub

To wash in warm water, the machine has to heat the water itself. The heating element sits in the bottom of the outer tub, under the drum. A temperature sensor plugged into its middle measures the water temperature, and once it is warm enough the control board (PCB) switches the element off. The element only comes on when covered with water, so if too little water has come in, the machine won't heat. Choose 60° and watch the water temperature rise slowly on the chart.

Go deeper: Heating: the element sits in the bottom of the tub

A heating element is usually about 1.8⁠–⁠2.2 kW [varies by model]. Work out its resistance with R = V²/P: at 220 V and 2 kW it is about 24 Ω, so measured cold it is usually 20⁠–⁠30 Ω. If it reads infinite, it has burnt out. More important is measuring the insulation to earth. Between the resistance wire and the metal sheath it should be in the megohm range, and you need an insulation tester to measure it properly. When scale makes the sheath overheat and crack, or damp gets in, the insulation drops. The typical symptom is that the RCD (residual-current device) trips as soon as heating starts.

How long does heating take? The specific heat of water is about 4.18 kJ/(kg·K). Say there are 12 L of water in the bottom of the tub, heated from 20°C to 60°C: 12 × 4.18 × 40 ≈ 2000 kJ, which takes a 2 kW element about 17 minutes. Add the clothes, the drum and the heat lost to the surroundings, and in practice it takes even longer. So a 60°C programme is long by nature. If heating takes absurdly long or the machine shows a heating timeout, first suspect the heating element, the temperature sensor or the relay on the control board (PCB).

The temperature sensor is most often an NTC (negative temperature coefficient) thermistor: the hotter it gets, the lower its resistance. At 25°C it can be anything from a few kΩ to a few dozen kΩ, depending on the brand (for example about 40⁠–⁠50 kΩ on LG, and Samsung has 10 kΩ types). At 60°C it falls to about a quarter to a third of that. When you measure it, compare it against a thermometer, and replace it if it is far off. In many designs the heating element circuit is also wired in series with the “heater-safe level” contact of the water level sensor (pressure switch) [varies by model]. Until the water is high enough, the control board can't power the element even if it wants to, so dry-fire protection doesn't rely on software alone.

5. Draining: the drain pump and filter

After the wash, the drain pump pulls the water out of the outer tub through the tub-to-pump hose (sump hose) and pumps it out of the back through the drain hose. In front of the pump, the drain filter catches coins, hairpins and necklaces. Once it clogs, the water can't drain away: a common cause of “Won't drain”. The filter is behind the small flap at the bottom of the front, on the right or the left depending on the brand (bottom right on this 3D model); press “Filter flap” to open it and look.

Go deeper: Draining: the drain pump and filter

The drain pump most often runs on a single-phase permanent-magnet synchronous motor. Its rotor is a magnet that turns in step with the 50 Hz AC supply (with two poles, that is 3000 revolutions a minute). This kind of motor can start in either direction, so the impeller has straight radial vanes that pump water whichever way it turns. If you turn the impeller by hand, you feel some “free play” before it catches. That is by design, so the motor gets turning before it takes the load; it isn't a fault. But if the impeller turns off-centre and wobbles (which technicians call “ghosting”), the pump's rotor bushing is worn. Draining may still work, but the pump is noisy and needs replacing.

The pump itself is a centrifugal pump: the impeller flings the water against the pump housing and then pushes it out. It can usually lift water about a metre. Its power is usually a few dozen watts, and its coil resistance about 150⁠–⁠250 Ω, most often around 200 Ω [varies by model]. Judge by the sound. “Humming” but no water coming out most often means the drain filter or the impeller is jammed, or the impeller has come off. No sound at all: check the coil and whether the control board (PCB) is sending power. A “rattling” sound usually means something is caught in the pump chamber.

How does the control board know whether the water has drained? It watches the water level sensor (pressure switch). If the level hasn't dropped back to “empty” within a set time after the pump starts, it shows a drain error. So besides the drain filter, these all show the same error: a blocked tub-to-pump hose (sump hose), which sometimes has a sock stuck in it; a kinked drain hose; and a blocked floor drain. Before opening the filter, remember to put a shallow tray underneath to catch the water: it may still be very hot.

6. Spinning: centrifugal force throws the water out

Once the water has drained, the drum first turns at about 90 rpm for “Balancing load”, so the clothes spread evenly against the drum wall. Only then does it speed up to 400⁠–⁠1400 rpm. At 1400 rpm, the clothes against the drum wall feel about 537 times the force of gravity. The water is thrown out through the drum's holes, runs down into the outer tub and is pumped away. Drag the “Spin speed” slider and watch how the centrifugal force changes.

Go deeper: Spinning: centrifugal force throws the water out

Centrifugal force is expressed as “relative centrifugal force” (RCF): RCF = ω²r/g ≈ 1.118×10⁻⁵ × r(cm) × n². At r = 24.5 cm, 400 rpm gives about 44 g, 800 rpm about 175 g, 1000 rpm about 274 g and 1400 rpm about 537 g. Centrifugal force is proportional to the square of the speed: double the speed and the force becomes four times as big.

But the water thrown out doesn't rise in the same proportion. Water between the fibres comes out easily; water soaked up inside the fibres is very hard to shift. The EU energy label grades machines by “residual moisture content” (weight of water ÷ weight of dry clothes): class A is below 45%, class B 45⁠–⁠54%. Usually 1400 rpm gets down to about 45⁠–⁠55% and 1000 rpm to about 55⁠–⁠65% [approx.; varies by fabric and machine]. The higher the speed, the more the clothes wrinkle and the harder the drum bearings and shock absorbers work, so faster isn't always better.

During the spin the drain pump runs the whole time, because the water thrown out must be pumped away at once. If it drains slowly, the standing water drags on the drum and whips up foam, and the machine slows down or stops. So “Won't spin” isn't always a motor problem. Check the drain first. Then see whether the load is just one or two big towels or bath mats (the easiest loads to unbalance). Only then check the motor and the speed sensor (tacho).

7. Suspension: springs, shock absorbers and a block of concrete

If the wet clothes are spread unevenly at high speed, the whole outer tub swings hard. Two suspension springs (also called hanging springs) hang the tub from the top, the shock absorbers below soak up the vibration, and heavy concrete counterweights on top of and in front of the tub [varies by model] keep it steady. On the way up there is a resonance zone (from about 100⁠–⁠200 rpm up to 300-odd rpm, depending on the model) where the tub swings hardest, so the machine speeds straight through it. “Uneven” is on now: watch the machine rebalance, then lower its speed to protect itself.

Go deeper: Suspension: springs, shock absorbers and a block of concrete

The outer tub, together with the drum, the motor and the concrete counterweight, hangs as one unit from the suspension springs (also called hanging springs). It is a “spring–mass” system with its own natural frequency f = (1/2π)·√(k/m). A handy estimate: if the springs stretch by δ at rest, then f ≈ (1/2π)·√(g/δ). With δ of 3⁠–⁠5 cm, f is about 2⁠–⁠3 Hz, which is a drum speed of 100-odd rpm. In practice the tub has several vibration modes, swinging up and down, side to side and front to back, so there is a whole resonance zone [from about 100⁠–⁠200 rpm up to 300 rpm; to be confirmed; varies by model].

In the resonance zone, even a little imbalance makes the outer tub swing hard. So the programme first runs a “Balancing load” step at about 80⁠–⁠100 rpm (above the 60 rpm critical speed, so the clothes stay pressed to the drum wall). From the speed sensor (tacho), the control board (PCB) measures how the speed rises and falls within each turn and estimates how big the imbalance is. Only when it is small enough does the drum race through the resonance zone. If several tries fail, the machine lowers the top speed or skips the spin. Past resonance, the outer tub instead turns around the shared centre of mass. The amplitude is about imbalance mass × radius ÷ total suspended mass, for example 0.5 kg × 0.245 m ÷ 50 kg ≈ 2.5 mm. The concrete counterweight is there to make that denominator bigger.

On a front-loader the shock absorbers are most often friction dampers: felt friction pads on the piston (nicknamed “oil felt” by technicians, though no oil is involved) soak up energy by friction. This matters most in the few seconds of racing through resonance. A front-loader usually has two to four, depending on the machine (large-capacity machines tend to have more). Once the pads wear, the tub “bangs” hard as soon as the spin starts. On site, use the “basketball test”: press down inside the drum. If it bounces a few times before it stops, the shock absorbers are worn; normally there is resistance and the drum comes back up slowly. You can also take one out and push and pull it by hand: normally it should resist evenly and firmly. If it slides with no resistance, it is worn. Replace the whole set, however many there are. A new machine with its transit bolts still in, uneven feet or a floor that isn't solid can all cause similar violent shaking, so rule these out first.

8. Drive: the motor and belt

The motor hangs under the outer tub. Through the drive belt, it turns the big drum pulley (also called the flywheel) at the back. The drum pulley and the small motor pulley are in a ratio of about 10-plus to 1, turning the motor's high speed into a slow, strong turn of the drum. This is a brushed motor: two motor carbon brushes press on the commutator to feed in current, and they wear down with use. A belt that has come off and worn brushes both give “Drum won't turn”. With the belt off, the motor still turns but the drum doesn't move; with worn brushes, the motor twitches, sparks and stops.

Go deeper: Drive: the motor and belt

Traditional belt-driven machines most often use a series-wound (universal) motor: the stator coils and the rotor are connected in series through the motor carbon brushes. The current reverses in both at once, so the motor still turns on AC. Its torque is roughly proportional to the square of the current, which gives it strong starting torque. The control board (PCB) sets the speed by phase-angle control with a triac, which adjusts the voltage. The speed sensor at one end of the motor (most often a magnet and a coil, i.e. a tacho coil) reports the speed back, with a signal frequency proportional to the speed. Forward and reverse come from relays that swap how the stator and rotor are connected.

The ratio of the drum pulley (also called the flywheel) to the motor pulley is about 12⁠–⁠15:1. So with the drum at 1400 rpm, the motor has to turn at about 10,000-odd rpm; while washing at 50 rpm, the motor turns only 600⁠–⁠700 rpm. The belt is most often a poly-V belt. The size printed on it, for example “1195 J5”, means an effective length of 1195 mm, a J profile (rib pitch 2.34 mm) and 5 ribs. Some are elastic (stretch) belts with no tensioner, which you fit by “rolling” them on. If the belt keeps coming off, look beyond an ageing belt: also check whether the drum pulley wobbles (the bearings) and whether the motor bolts are loose.

Motor carbon brushes are consumables and usually last about 4⁠–⁠7 years. Once worn short, they spark, the motor loses power and stops now and then, and the control board shows a motor error. Worn brushes can also just keep the spin from reaching high speed, with no error code. The rotor (measured through the carbon brushes) and the stator coils are about 1⁠–⁠5 Ω. The speed sensor coil is about a few dozen to 200-odd Ω [varies by model]. Measure while turning slowly: if the reading suddenly jumps to infinite, the commutator may have an open segment or a brush may be making poor contact. If the motor still won't turn after new brushes, check the commutator too. Newer machines mostly use a brushless DC (BLDC) inverter motor, with a belt or direct drive. It has no brushes, saves power and runs quietly. An inverter board drives its three-phase windings, and the resistance between each pair of phases should be the same. Before removing the inverter board, wait for the capacitors to discharge: the DC bus is at about 300 V.

9. From symptom to part

On a call-out, the technician starts from the symptom to find the part. In the “Fault simulator”, pick a symptom customers often report: the 3D model acts it out and lights up the parts involved. Then press “Start repair” to see how it is fixed. Showing now: “Won't drain”. The drain filter is clogged, so the drain pump keeps “humming” but the water can't get out, and the machine stops. With water covering the door seal, the door lock won't unlock either.

Go deeper: From symptom to part

Finding the part from the symptom follows a fixed order: Look → Reproduce → Isolate the system → Cheap and easy first → Confirm, then replace. Step one is to ask and look. When did it start? At which step of the programme does it go wrong? Are there odd noises or smells, flashing lights or an error code on the panel? Has the machine been moved lately, and what was put in it? Then run it yourself and see in which stage the symptom appears: filling, washing, draining or spinning. When the customer says it “won't move” or “won't drain”, that may not be the same thing you see.

Next, sort the symptom into a system. At every step, the control board (PCB) waits for a sensor to report “done” before it moves on. Filling waits for the water level sensor (pressure switch) to report enough water, and heating for the temperature sensor to report the water temperature. Draining waits for the water level sensor to report “empty”, and spinning for the speed sensor (tacho) to report the speed. Before filling, the door lock (interlock) must also report that it is locked. So an error code usually only tells you which step timed out or which reading is wrong, not which part has failed. The same symptom can come from different systems. “Won't spin” can be slow draining or an unbalanced load, or it can be the motor carbon brushes. “Door won't open” can be a faulty door lock, or simply water still in the tub, which must drain before the door unlocks.

Rule out the possibilities one by one, starting with what is cheap, easy and common. First check the settings and how the machine is used (programme, load size, detergent, whether the tap is on, whether the drain hose is kinked or siphoning). Next, clean the spots that need no new parts, such as the drain filter and the inlet filter screen of the water inlet valve. Only then take the machine apart and test parts: with the power off, measure resistance and continuity; with the power on, see whether the control board is sending power. Have evidence before you replace a part, for example a coil that reads open circuit or a shock absorber that slides with no resistance. After the replacement, run a programme again: the job is done only when the symptom has gone. Every symptom in the “Fault simulator” above works this way: symptom → system → part → repair.

Common faults

Washer: one cause of “Won't drain”

Cause: Coins and hairpins are clogging the drain filter, so the water can't reach the drain pump.
What you see: The drain pump runs with a “humming” noise, but not a drop of water leaves the outer tub. After a while the machine stops.
What the technician does: The technician first lets the water out of the tub, opens the filter flap, unscrews the drain filter, clears out the debris and fits it back.

Repair: Clean drain system

Washer: one cause of “Drum won't turn” — Belt came off

Cause: The drive belt has fallen off into the bottom of the machine, so the motor's turning force can't get to the drum pulley.
What you see: The water is in and the motor still turns, but the drum doesn't move at all. Turned by hand, the drum spins like a windmill, with no resistance.
What the technician does: The technician takes off the back panel and loops a new drive belt over the motor pulley and the drum pulley (the old belt goes back on only if no suitable belt is available and the old one is undamaged).

Repair: Replace drive belt

Washer: one cause of “Drum won't turn” — Worn brushes

Cause: The motor carbon brushes have worn short. They no longer press firmly on the commutator, so the motor doesn't get enough current.
What you see: The water is in, and the motor twitches and sparks, but the drum just won't get going.
What the technician does: The technician takes out the carbon brushes on both sides of the motor and fits a new pair.

Repair: Replace motor carbon brushes

Washer: one cause of “Shaking badly”

Cause: The felt friction pads in the shock absorbers have worn away, so nothing soaks up the swinging of the outer tub.
What you see: As the spin speeds up through the resonance zone, the outer tub swings hard and knocks the cabinet, and the whole machine jumps.
What the technician does: The technician first rules out uneven feet, confirms the shock absorbers have failed with the “basketball test”, then replaces the whole set.

Repair: Replace shock absorber

Washer: one cause of “Won't fill”

Cause: The filter screen in the inlet of the water inlet valve is clogged with sand and rust.
What you see: The tap is on and the water inlet valve is open too, but the water only dribbles in, and it takes ages to reach the water level.
What the technician does: The technician takes off the inlet hose, pulls the filter screen out of the water inlet valve with long-nose pliers and cleans it.

Repair: Clean water inlet system

Washer: one cause of “Door leaking”

Cause: There's a hole in the bottom of the door seal, so it leaks once the water rises above it.
What you see: During the wash, water drips from the door at the 6 o'clock position and pools on the floor.
What the technician does: The technician fits a new door seal.

Repair: Replace door seal

Systems

Water inlet

Inlet hose → water inlet valve → detergent drawer → detergent hose → outer tub. The vent hose lets air pass between the drawer and the tub. When the water level sensor measures enough water, it tells the control board to switch off the water inlet valve.

Parts involved: Inlet hose, Water inlet valve, Jet cover, Detergent drawer, Drawer handle, Detergent hose, Vent hose, Water level sensor, Level sensor hose

Drain

Outer tub → tub-to-pump hose → drain filter → drain pump → drain hose.

Parts involved: Tub-to-pump hose, Drain filter, Drain pump, Drain hose

Drive

Current fed through the carbon brushes turns the motor, the drive belt turns the drum pulley, and the shaft and spider turn the drum. The drum bearings carry the whole shaft.

Parts involved: Motor, Motor carbon brushes, Motor connector, Speed sensor, Drive belt, Drum pulley, Drum spider and shaft, Drum bearings

Drum and tub

The outer tub holds the water and doesn't turn. The drum turns inside it with its drum paddles, held up at the back by the spider, the shaft and the drum bearings.

Parts involved: Outer tub, Drum, Drum paddle, Drum centre cap, Drum spider and shaft, Drum bearings

Suspension

The suspension springs hang the outer tub, the shock absorbers below soak up vibration, and the concrete counterweight keeps it steady.

Parts involved: Suspension spring, Shock absorber, Concrete counterweight

Door

The door hinge carries the door, and the door handle pulls the door hook free. The door lock locks the door hook before the wash starts, and the door seal does the sealing.

Parts involved: Door glass, Door frames, Door hinge, Door handle, Door hook, Door lock, Door seal

Heating

The heating element heats the water in the bottom of the outer tub, the temperature sensor measures the water temperature, and the control board switches the element off when the water is warm enough.

Parts involved: Heating element, Temperature sensor

Controls

The programme knob, the buttons and the control panel connect to the control board, which directs filling, turning, heating, draining and door locking. The leak sensor in the base also reports to the control board.

Parts involved: Control board, Control panel, Programme knob, Panel buttons, Start button assembly, Power button, Leak sensor

Power

Plug → power cord → mains filter → control board.

Parts involved: Plug, Power cord, Mains filter

Parts

Cabinet: The steel outer casing: the front panel, worktop, two side panels and back panel are fastened together, and every part fits inside. The suspension springs hang from the top of the cabinet.
Control panel: The plastic fascia where you choose the programme (without the buttons, which are a separate set of parts). The control board (PCB) sits right behind it.
Programme knob: Turn it to choose the wash programme. On many models, turning it also switches the machine on and off.
Panel buttons: Buttons for functions such as water temperature and spin speed.
Start button assembly: The “Start/Pause” button. Press it and the machine locks the door first, then starts the programme.
Power button: A separate on/off button. Not every machine has one; some switch on with the programme knob.
Control board: The control board (PCB) is the machine's “brain”: it controls filling, shutting off the water, turning, draining, motor speed, wash time, and locking and unlocking the door. Some machines split it into several boards (for example power supply, motor and display modules).
Detergent drawer: A pull-out drawer with three compartments (main wash, softener and pre-wash; the order varies by model). When the machine fills, tap water flushes through it and carries the powder or liquid detergent down the detergent hose (dispenser hose) into the outer tub.
Drawer handle: The handle on the front of the detergent drawer, pulled out and pushed in every day.
Jet cover: The splitter lid on top of the detergent drawer. It sends the high-pressure water from the water inlet valve to different compartments, flushing different detergents at different times.
Water inlet valve: A solenoid valve at the back, where the inlet hose connects. It opens only when the control board (PCB) powers it and closes as soon as the power stops, so without power no water comes in, even with the tap on. It has two or three coils, each feeding a different drawer compartment, and a filter screen in its inlet keeps sand out.
Inlet hose: The hose from the tap to the water inlet valve at the back.
Detergent hose: The detergent hose (dispenser hose) is the corrugated hose linking the detergent drawer to the outer tub; the detergent water flushes down it into the tub.
Water level sensor: The water level sensor (pressure switch) measures the level from air pressure: the deeper the water, the higher the air pressure in its hose. At the right level it tells the control board (PCB) to switch off the water inlet valve, and the drum starts turning to wash.
Level sensor hose: The thin hose from the bottom of the outer tub up to the water level sensor (pressure switch), carrying the water pressure up to it.
Door glass: Thick glass that bulges inwards. You can see into the drum through it, and its slope pushes the clothes back in, so they don't gather at the door seal or the door.
Door frames: The outer frame and inner frame of the door clamp the glass between them (some models also have a middle frame, three in all).
Door hinge: Carries the whole door and lets it open and close smoothly.
Door handle: The handle you pull to open the door (also called the door pull). On models with a handle, the door handle moves the door hook through a lever.
Door hook: The hook on the back of the door. When you shut the door it catches in the door lock (interlock), so the door can't spring open. There are moving types (which move with the door handle) and fixed types.
Door lock: The door lock (interlock) senses whether the door is shut. When a programme starts, it locks the door hook, and the machine fills and turns only once the lock is confirmed. It unlocks only when the programme ends and the drum has stopped. There are two types. A delayed-release lock unlocks about two or three minutes after the programme ends, with only a very faint “tap”. An instant-release lock goes by the water level: once the water is low enough, it unlocks at once with a clear “click”.
Door seal: The folded rubber ring between the door and the outer tub. It flexes as the tub swings and seals against leaks at the same time.
Outer tub: The sealed plastic tub around the drum. It doesn't turn; it holds the water. Together with the drum, the motor and the concrete counterweight, it hangs from the suspension springs.
Drum: A stainless-steel cylinder with small holes and a pressed pattern, held up by the three-arm bracket (spider) and shaft at the back. It turns slowly to tumble the clothes during the wash, and fast to throw the water out during the spin.
Drum paddle: Three raised plastic pieces inside the drum, mostly triangular. As the drum turns, they flip the clothes over and lift them up.
Drum centre cap: On some front-loaders, a plastic cover in the middle of the back of the drum that hides the screw at the bearing position.
Drum spider and shaft: The metal three-arm bracket (spider) on the back of the drum joins the shaft in the middle, which runs through the bearings in the back of the outer tub and holds up the whole drum. When Fixes says “drum shaft”, it includes the spider and the bearing seat.
Drum bearings: The ball bearings in the back of the outer tub: a front-loader usually has two of different sizes (the one nearer the drum is bigger), with a shaft seal in front; a top-loader usually has a pair. They let the drum turn at high speed quietly, with almost no friction.
Drum pulley: The drum pulley (also called the flywheel) is the big pulley on the end of the shaft. Its ratio to the small motor pulley is about 10-plus to 1, so the motor can turn a whole drum of wet clothes with little force.
Drive belt: Carries the motor's turning to the drum pulley. Models with a direct-drive inverter motor have no belt.
Motor: Mounted under the outer tub, it swings with the tub. It turns electrical energy into rotation and drives the drum through the drive belt; the control board (PCB) sets its speed and direction.
Motor carbon brushes: A pair of carbon blocks, pressed by springs against the motor's commutator, that feed current into the turning coils.
Motor connector: The wiring connector on top of the motor, wired to the control board (PCB).
Speed sensor: The speed sensor (tacho) at one end of the motor measures the motor's speed, so the control board (PCB) can control it.
Heating element: The electric heating tube in the bottom of the outer tub, fitted from the back, that heats the water. It only comes on when covered with water.
Temperature sensor: The sensor that measures the water temperature. It plugs into the middle of the heater flange and reports the water temperature to the control board (PCB).
Drain pump: Pumps the water from the outer tub out of the machine through the drain hose. A front-loader can't drain without it.
Drain filter: Behind the small flap at the bottom of the machine's front, on the right or the left depending on the brand (LG, for example, is most often bottom left; this 3D model has it bottom right). During draining it catches coins, hairpins, necklaces and other debris, protecting the drain pump. Clean it regularly.
Tub-to-pump hose: The tub-to-pump hose (sump hose): the thick hose from the bottom of the outer tub to the drain pump.
Drain hose: The grey hose from the drain pump outlet to the household drain. It hangs high at the back to stop water flowing back.
Vent hose: The air hose at the top of the machine (a white, see-through plastic hose). It runs from the back of the detergent drawer down to the outer tub and lets air pass between the drawer and the tub. The water level sensor hose is sometimes called an “air hose” too; don't mix them up.
Suspension spring: The suspension springs (also called hanging springs) hang the whole outer tub from the top of the machine, carrying its weight and absorbing vibration too.
Shock absorber: Braced between the bottom of the outer tub and the base, it cushions and soaks up the swinging during the spin. A front-loader usually has two to four, depending on the machine (large-capacity machines tend to have more). Inside, a felt friction pad (nicknamed “oil felt” by technicians, though no oil is involved) soaks up the energy by friction.
Concrete counterweight: The concrete counterweight is a heavy block of concrete that makes it harder for an uneven load of wet clothes to swing the outer tub about. There can be one on top of the tub and one at the front [varies by model].
Leak sensor: A float switch in the base tray. When a leak inside the machine collects in the base, the water lifts the float and triggers the switch, so the control board (PCB) knows at once there is water in the base, and stops the machine or drains the water.
Power cord: The cable from the cabinet to the plug.
Plug: The 13A three-pin plug, with a fuse inside.
Mains filter: The mains filter (EMI filter) sits where the power comes into the machine: capacitors and coils inside filter out electrical noise on the power line.
Clothes: Lifted by the drum paddles and dropped again during the wash; pressed against the drum wall by centrifugal force during the spin.