“I stopped rinsing dishes before the dishwasher” – what happened next shocked even appliance engineers

Amelia Foster • January 23, 2026 07:01

Standing at the sink one evening, I caught myself doing it again: hot tap on full, plates under a furious spray, every smear chased away before the dishwasher ever saw it. It felt responsible, almost virtuous – the way my parents did it, the way “proper” adults treated their crockery.

Then our water bill nudged upwards, and a visiting appliance engineer sighed when he saw me rinsing.

“Do you want the short version?” he asked. “You’re undoing half the engineering in that machine.”

So I stopped. For a full month, through roast dinners, lasagne, curry and the odd burnt cheese tragedy, I loaded plates dirty – just scraped, never rinsed. I tracked smells, filter gunk, streaks on glasses, even the water meter.

What happened next did not just surprise me. When I showed the results to two dishwasher engineers, they admitted they were “quietly stunned” that the machine had behaved exactly as the design team had hoped, but almost never sees in real homes.

How we fell in love with the pre-rinse

Most of us learned dishwashing from someone who grew up before modern machines. Older units needed help: weaker pumps, simpler sprays, basic detergents. Leaving last night’s gravy on a plate really could mean scraping it off the next morning.

That message stuck.

Food on plate = lazy.
Clean-looking plate in dishwasher = responsible.
Running the tap for five minutes = just “being thorough”.

The trouble is, dishwashers changed faster than our habits. Enzymes got smarter, spray arms more aggressive, sensors more sensitive. Yet the old reflex remained: scrub first, then let the machine “finish”.

We still treat dishwashers as timid helpers, when many are actually built to be the main act.

I went into my no-rinse month expecting at least a minor domestic disaster. What I got instead was a crash course in how these machines are meant to work.

What really happened when I stopped rinsing

Week 1: braced for carnage

For the first few days, I hovered over every cycle. I used my usual tablets, my usual eco programme, nothing fancy. Plates went in with visible sauces, dried rice, traces of egg, a fair bit of melted cheese. I scraped the worst off with a spatula – no water involved.

The results?

Plates: clean, even at the edges.
Glasses: actually clearer, with fewer faint streaks.
Smell: nothing unusual when I opened the door.

The only obvious difference was psychological. It felt wrong to close the door on what looked like chaos.

Week 2: the filter test

By the second week, I started checking the filter every few days. If all that extra food really was a problem, this is where it would show.

Instead of being choked with gritty sludge, the filter held:

The usual sweetcorn skins and onion bits.
A few pasta fragments.
Thin, soft residue that rinsed off easily.

The engineer who had first told me to stop rinsing had a simple explanation: most of what I used to rinse down the sink was never reaching the dishwasher filter at all. It went straight into the drain, dragging litres of hot water and energy with it.

“You’re not protecting the machine when you pre-rinse,” he said when I sent photos. “You’re protecting the drain.”

Week 3–4: the numbers that startled the engineers

I have a simple digital water meter, so I compared a “typical” rinsing month with my no-rinse experiment. The household stayed the same: same people, same meals, same number of loads.

Roughly, here is what happened:

Habit	Change observed	Likely reason
No pre-rinsing	Household water use down by 10–15%	Fewer minutes with hot tap running
Same programmes as before	Dishes consistently cleaner at corners and backs	Sensors saw more soil and washed more assertively
Filter checks	No increase in serious clogs	Machine designed to handle typical food residues

When I showed this to an appliance engineer friend and a colleague of his, both said almost the same line:

“We design for this, but almost no-one trusts the machine enough to try.”

What shocked them was not that it worked, but that, given the chance, the dishwasher behaved almost exactly as the lab tests predicted – in a normal, messy family kitchen.

Why modern dishwashers dislike pre-rinsed plates

Dirt as a signal, not a failure

To most owners, a dirty plate going into the dishwasher feels like a risk. To the sensors inside the machine, it is simply information.

Many modern dishwashers use:

Turbidity sensors that “look” at how cloudy the water is.
Flow and pressure sensors that monitor how hard the pump is working.
Pre-set soil levels in their programmes, assuming a normal amount of grime.

When you pre-rinse, you remove the very thing those systems expect.

The water looks cleaner than it should.
The programme may shorten the main wash or drop the temperature.
Detergent enzymes never meet enough food to fully activate.

The result can be exactly what pre-rinsers fear: faint films on glasses, cloudy cutlery, a sense that the machine is “not what it used to be”.

Detergent chemistry that wants something to chew

Enzyme-based detergents are formulated to break down starches, fats and proteins. They perform best:

At specific temperatures.
With a certain amount of food soil available.
Over a set contact time.

Feed them a load of already-rinsed plates and you change all three. The detergent ends up doing less cleaning and more gentle bathing. You have effectively paid for chemistry you then deny the chance to work.

A senior chemist from a detergent manufacturer once summed it up bluntly: “If you insist on rinsing, at least buy cheaper tablets. You’re wasting the good ones.”

The no-rinse routine: step by step

Not rinsing does not mean throwing a baking dish in with half a lasagne still attached. The trick is to give the machine the sort of challenge it is built for, not an industrial accident.

1. Scrape, do not scrub

Use a silicone spatula, wooden spoon or old card to push leftovers into the food caddy.
Flick off big bones, citrus peels and eggshells – these belong in the bin or food waste.
Avoid running water unless something is genuinely welded on.

2. Load with the spray in mind

Plates face the centre, slightly angled, so jets can reach both sides.
Bowls go at an angle, not nested.
Pans and baking trays sit at the sides or back, not blocking the middle spray.

Crowding is the enemy here. If water cannot reach, it cannot clean – rinsed or not.

3. Choose programmes that match reality

Use eco or auto for everyday loads with typical food on them.
Reserve quick 30–60 minute programmes for lightly soiled glasses and plates after snacks.
For lasagne, roasts and curries, do not be shy of the intensive or “pots & pans” setting.

If you are loading genuinely dirty items, give the machine the cycle it deserves.

4. Let the machine finish its job

Resist opening the door mid-cycle “just to check”.
Keep salt and rinse aid topped up; they help water behave better on glass and steel.
Clean the filter once a week with a brush under the tap – 60 seconds that keeps everything flowing.

A dishwasher with a clean filter and a decent tablet can deal with more than most owners will comfortably admit.

When you should still rinse or soak

There are cases where a little human intervention still makes sense. Engineers were clear about this when I asked.

You should at least rinse or soak when:

Food has been baked on repeatedly, like a casserole dish used several times before washing.
Plates have sat for days and the residue has hardened like cement.
You are dealing with burnt sugar, jam or caramel, which can glue itself on.

In these situations:

A brief soak in cold or lukewarm water (not boiling) loosens the worst.
A quick scrape afterwards usually brings the item back into “normal dirty” territory.

If you only run the dishwasher every two or three days, a short pre-wash cycle can help prevent smells and flies without standing at the sink. Most machines have one; it uses far less water than a manual rinse under the tap.

What changed in daily life

After the first awkward week, the new routine felt strangely calm. No more “rinse queue” at the sink while someone else tried to load the rack. No arguments about whether this sauce or that curry “needed a scrub first”.

The gains were quiet but very real:

Time: I saved several minutes per load, often at the most hectic times of day.
Water and energy: the meter dropped, and our combi boiler fired up less often for pointless pre-rinsing.
Results: glasses stopped coming out with that faint, greasy halo at the base; the cutlery tray looked brighter.

The engineers’ verdict, after four weeks of photos, notes and filter inspections, was oddly flattering to the machine:

“This,” one of them wrote back, “is the first time in a while I’ve seen a domestic dishwasher being used the way we actually designed it to be used.”

Thinking differently about “clean”

The real shift was not technical. It was mental. Letting the dishwasher see real dirt felt, at first, like lowering standards. In practice, it meant raising my expectations of the appliance I had already paid for.

Instead of doing half the job myself and then complaining quietly about streaks, I now:

Trust the engineering enough to give it proper work.
Spend less time at the sink and more time actually eating with the people I cooked for.
Check the filter and salt rather than chasing every breadcrumb off a plate.

Once you stop rinsing, you realise how much of that ritual was about habit and anxiety, not hygiene. The machine cannot surprise you with what it can do until you give it something real to tackle.

FAQ:

Will food scraps block my dishwasher or pipes if I stop rinsing? Modern dishwashers are designed to handle typical food residues. Large bones, fruit stones and eggshells should still go in the bin or food caddy, but normal sauces, bits of pasta and crumbs are filtered and ground before draining. Regularly cleaning the filter is far more important than pre-rinsing.

Does not rinsing make the dishwasher smell? In most cases, no. Smells usually come from a dirty filter, standing water in rarely used machines or pipes, and low-temperature washes only. Run an occasional hot maintenance cycle and keep the filter clean; this matters more than rinsing plates first.

Is it safe for hygiene to put very dirty plates straight in? Yes, provided you run an appropriate programme with good detergent and salt where recommended. Dishwashers reach higher temperatures than most people use by hand and maintain them for longer, which is more effective for hygiene than a brief hot rinse under the tap.

Are there dishes I should still wash by hand? Wooden boards and utensils, delicate crystal, certain plastics and anything labelled “not dishwasher safe” should stay at the sink. That advice does not change whether you pre-rinse or not – it is about material, not dirt level.

Do eco programmes really cope with un-rinsed dishes? Eco and auto programmes are designed for normally soiled loads. They may run longer at lower temperatures, but they adjust water use and time based on how dirty the water is. Giving them realistic dirt actually helps them make the right adjustments.