Last Updated on October 26, 2026 by Umar Farooq
Load sensing is your washing machine weighing the laundry before it decides anything else, and it happens before a single drop of water enters the drum.
That one design decision is responsible for most of the confusion around this stage. A machine from twenty years ago filled to a fixed level the moment you pressed Start, so water arriving was proof that something was working. A modern machine has to know the weight first, because the weight determines the water. So the first thing it does is nothing you can see — it rocks the drum, listens to the motor, and thinks. To a person standing in front of it, thinking and being broken look identical.
This page explains the stage itself: what is being measured, what the clicking is, how long about a minute actually means, and why a duvet defeats it. If your machine genuinely never leaves sensing — several minutes, every cycle, whatever you put in it — that is the fault case, and it is covered separately in washing machine stuck on sensing.
What washer load sensing is actually measuring
There is no scale under the drum. Nothing in a domestic washing machine weighs laundry the way a bathroom scale weighs you, and adding something that could would be expensive and fragile. Instead the machine uses the part it already has and already controls precisely: the motor. It gives the drum a short push, measures how hard the motor had to work to get it moving and how quickly it coasted back to a stop, and converts that resistance into an estimate of mass. Heavy load, more effort and a faster stall. Light load, less of both.
That estimate is the input to almost every decision the cycle makes afterwards. Water level is the obvious one — an HE machine adds water proportional to what it believes is in there, which is exactly why the correct level so often sits below the door glass and looks wrong. But the same number also sets wash duration, how aggressively the drum tumbles or the wash plate turns, how many rinses are worth running, and how gently the spin has to ramp up. Get the weight wrong and all five of those come out wrong together. Nowhere does that matter more than on an HE top-load washer, where the whole design rests on washing properly in a few inches of water the sensor decided on.
On many machines the pressure sensor then checks the guess during fill. The machine adds water, watches how fast the level rises, and quietly corrects itself if the laundry is absorbing more or less than the weight predicted. So sensing is not really one measurement. It is a first estimate that the machine keeps testing against reality for the rest of the wash — which is exactly why the time on the display moves, covered in why your washer adds time mid-cycle.
| What sensing sets | How the weight affects it | What you notice if it reads high |
|---|---|---|
| Water level | Volume scales with estimated load mass | More water than the load looks like it needs |
| Wash duration | Longer for heavier loads | Displayed time jumps upward early |
| Tumble or agitation pattern | Gentler and slower for large loads | Drum movement looks lazy |
| Number of rinses | Extra rinse on heavy or absorbent loads | Cycle runs past its original estimate |
| Spin ramp | Slower acceleration, more balance checks | Long pauses before the spin builds speed |
What the clicking is
The clicking is mechanical, it is normal, and on a top-loader it is usually the drive system engaging rather than anything electronic. Before the wash plate can turn the drum in either direction, the gears connecting motor to plate have to line up. The motor nudges, the gear teeth find each other, and each attempt produces a distinct click. Repeat that a dozen times in a minute and you get the sound that sends so many people searching, convinced something is grinding itself apart.
Front-loaders are quieter about it. There is usually no clutch to engage, so what you hear instead is the drum rocking a few degrees one way, pausing, and rocking back — with the machine measuring during each of those short movements. The pauses between them are not hesitation. They are the machine reading the result of the push it just made before deciding what the next one should be.
The distinction worth holding on to is between clicking and grinding. Clicking is discrete, evenly spaced, and stops when sensing ends. Grinding is continuous, gets louder as the drum speeds up, and carries on into the wash. The first is the machine working. The second is a different article.
How long sensing should take
LG publishes the actual figure, which makes this unusually easy to settle: “The load sensor operates for about 1 minute before water is supplied,” after which the drum rotates for roughly 30 seconds to detect weight (noises during load sensing — top load washer). Most other manufacturers do not document a number, but the mechanism is common enough across the category that the order of magnitude carries. A minute of quiet clicking is the norm. Two minutes is the outer edge of normal.
The reason that minute feels far longer than it is comes down to what you are shown, which is usually nothing. Some machines display a sensing indicator with no timer, so you have no reference for how far through it is. Others show an estimated cycle time that has not been calculated yet and therefore sits still. Nothing moves, nothing fills, nothing counts down, and the natural conclusion is that nothing is happening.
The most common way people turn a normal minute into a long one is by interrupting it. Pressing Cancel and starting again does not skip sensing — it restarts it from the beginning, so a machine that looked stuck for forty seconds is now genuinely three minutes into a process that should have finished twice by now. If you want to know whether sensing is working, time it once without touching anything.
Why no water arrives while it senses
Water arrives after the weighing because water would ruin the weighing. The motor is measuring resistance to movement, and a drum with water in it resists differently — sloshing mass shifts during the rotation, laundry gets heavier as it absorbs, and the reading changes from one moment to the next. The only point in the cycle where the machine can take a clean reading is the moment before anything has been added. So it takes it there, then fills to the level that reading justifies.
This is also why loading already-wet laundry throws the whole cycle out. The machine has no way to separate water weight from laundry weight; it assumes what it is weighing is dry, because that is the only assumption available to it. LG’s documented example is worth quoting for scale: a load of dry towels estimated at 30 minutes jumps to an estimated 1 hour 52 minutes once the machine detects the laundry is already wet (LG frontload washer — wash time keeps extending). Nothing has failed. The machine sized the cycle for roughly twice the laundry you actually gave it, because that is what it felt.
The practical consequence for anyone watching the drum through the glass: dry during sensing is the expected state, not a symptom. Whether water ever arrives is a separate question, and it belongs to the fill system rather than to the sensor.
Why one bulky item confuses it
A single duvet, a mattress protector or one heavy coat is the hardest thing you can ask a load sensor to measure. The machine takes several readings and expects them to broadly agree. A bulky item does not stay where it was put — it slumps, unfolds and redistributes with every push of the drum, so the resistance the motor feels is different each time. The machine gets three answers to one question, discards them, and tries again. That is why bulky loads sit in sensing longest, and why adding a second similar item usually settles it at once.
The opposite extreme causes the same stall for the opposite reason. Loads under roughly three to five pounds barely move the needle at all: the difference in motor effort between that and an empty drum is small enough to sit inside the sensor’s own noise, so the machine cannot confidently tell a light load from no load. Overloading fails a third way — a drum packed solid cannot move far enough for a reading to be taken, so the measurement never completes rather than completing wrongly.
There is a load size at which all of this works well, and LG states it plainly: about two-thirds of capacity (LG frontload washer — wash time keeps extending). That is not a comfort figure. It is the range in which laundry can move freely enough to be measured, redistribute itself when asked to, and still be reached properly by water and detergent.
When it is genuinely stuck rather than doing washer load sensing
Everything above describes a machine that eventually gets its answer and moves on. The line between normal and faulty is not the noise, the dry drum or the pauses — it is progression. Sensing that completes within a minute or two and hands over to fill is working, however odd it sounds while it does it. Sensing that runs for many minutes on every cycle, with a normal evenly spread load, is not sensing any more.
Two patterns get mistaken for a sensor problem often enough to be worth naming. The first is a machine that finishes sensing perfectly and then sits there because no water is available to it — a closed tap or a restricted inlet strands the cycle at the same visible point, which makes a fill problem look like a sensing one. The second is a machine that seems slow because it re-checks the load repeatedly later on, which is a balance and timing issue rather than a measurement failure.
- Never progresses past sensing, whatever the load: washing machine stuck on sensing
- Sensing completes but no water arrives: washing machine not filling with water
- Water arrives, but far too slowly: washing machine fills too slowly
- Cycle runs far past its estimate: washing machine stops mid cycle
FAQ
How long should load sensing take?
About a minute before water is supplied, plus roughly 30 seconds of drum rotation on LG machines. Two minutes without progress is where it stops being normal.
Is clicking during sensing a problem?
No. On top-loaders it is the drive gears aligning before the wash plate can turn, and it should stop when sensing ends.
Why is there no water while it senses?
Because water changes the weight it is trying to measure. The only clean reading available is the one taken before filling.
Why does the estimated time change after sensing?
The estimate is calculated from the weight the sensor just measured. Until that measurement exists, the number on the display is a placeholder.
Can I skip sensing?
No, and cancelling during sensing restarts it rather than skipping it. Some machines offer a manual water-level setting on certain cycles, which changes the fill but not the weighing.
Why does one duvet take so much longer than a full load?
It shifts position during every test rotation, so each measurement disagrees with the last and the machine keeps re-checking. A second similar item resolves it.
It senses fine but never fills. That is the fill system, not the sensor. See washing machine not filling with water.
