A dishwasher is judged on three things: what it takes, what it consumes and what you can hear. The rest, wash options and connectivity, changes little day to day. Here is how to read the stated figures, starting with the two that cause the most confusion, the place setting count and the energy class.
The place setting, a standardised unit
Dishwasher capacity is expressed in place settings, and this is not a marketing estimate: the place setting is a standardised set of crockery, comprising plates, a glass, a cup, a saucer and pieces of cutlery, used to measure every appliance under the same conditions.
A 60 cm wide machine generally states between 12 and 15 place settings, which suits a household of four to six. A 45 cm model sits around 9 to 10 settings, a size suited to one person, a couple or a narrow kitchen.
The trap is choosing small to save money. An undersized dishwasher runs more often, sometimes half empty, which consumes more overall than a larger machine run full. The rule is to size for your heaviest meals, not for the average.
Look too at the real capacity of the upper basket and whether a third cutlery drawer is fitted. Two machines both rated at 14 settings can behave very differently faced with tall items, mixing bowls or a baking tray.
- The place setting is standardised and comparable between models
- 60 cm: 12 to 15 settings, for four to six people
- 45 cm: 9 to 10 settings, for one or two people
- Size for heavy meals; a small machine simply runs too often
Freestanding, built-under or fully integrated
A freestanding appliance simply slides into place, with its own front panel and top. It can be moved, sold on and replaced without touching the kitchen.
A built-under appliance fits below the worktop without its own top. It lines up with the rest of the units and its control panel stays visible on the front, so you can read the cycle status at a glance.
A fully integrated appliance takes a door panel matching the units and its controls sit on the top edge of the door, so they are invisible when closed. The kitchen gains in unity, but you then need a light projected on the floor, or an app, to know where the cycle stands.
Always check the available height for the housing and the door swing clearance, particularly opposite an island or in a narrow passage.
Reading the energy label, rescaled since 2021
Since March 2021 dishwashers have been rated on a deliberately demanding A to G scale: the former A+, A++ and A+++ classes have gone, and an appliance once rated A+++ frequently lands at C or D on the new grid. A dishwasher rated C is therefore not a poor appliance, it is simply measured differently.
The label states energy consumption in kWh per 100 cycles, no longer per cycle: divide by one hundred for a single eco cycle. It also gives water consumption in litres per cycle, the duration of the eco programme, the capacity in place settings and the airborne noise class.
The noise class runs from A to D and appears next to the value in decibels. That is valuable information in an open-plan kitchen or where the machine runs overnight.
Every model is registered in the European EPREL database, searchable from the identifier printed on the label. That is the source to consult when checking a figure, rather than a sales sheet.
- A to G scale since March 2021, no more A+ or A+++
- Consumption quoted per 100 cycles of the eco programme
- Water in litres per cycle, programme duration, noise class A to D
- Figures verifiable in the European EPREL database
Why the eco programme is the longest and the most frugal
This is the commonest question, and the answer is counter-intuitive. The eco programme washes for longer at a lower temperature. In a dishwasher, most of the energy goes into heating the water, not into running the pump.
Lengthening the cycle in order to lower the temperature is therefore an excellent trade: the extra time costs very little, the heating avoided costs a great deal. A three to four hour eco cycle uses appreciably less than a one hour quick cycle.
It is also the eco programme that serves as the reference for every figure on the energy label. The stated values do not describe the intensive or the quick cycle, whose consumption is significantly higher.
The quick programme keeps its use for lightly soiled crockery you want back quickly. It is not the everyday programme, and using it systematically cancels out the benefit of a well-rated appliance.
An eco cycle run overnight, or during the day if you generate your own electricity, combines the best of both: duration no longer matters and consumption stays minimal.
- Heating the water dominates consumption, not the duration
- Eco cycle: longer, cooler, markedly more frugal
- Every label figure refers to the eco cycle
- The quick programme is a stopgap, not a habit
Drying, the main gap between ranges
Washing is now very consistent from one appliance to another. Drying is what separates the ranges.
Condensation drying, the most widespread, uses the residual heat of the load: water evaporates and condenses on the cooler walls of the tub. It is frugal and silent, but plastics, which hold little heat, often come out damp.
Fan-assisted drying with a heating element gives a better result at the cost of higher consumption. Some appliances open the door slightly at the end of the cycle to let moisture escape: simple, effective and free in energy terms.
Zeolite drying, using a mineral that releases heat as it absorbs moisture, gives the best result on plastics with no notable energy penalty. It is found on upper ranges.
One piece of advice applies to every machine: opening the door for a few minutes at the end of the cycle improves drying far more than any option, and costs nothing at all.
- Condensation: frugal and silent, plastics often damp
- Auto-opening door: simple, effective, no extra energy
- Zeolite: the best result, especially on plastics
- Opening the door at the end of the cycle remains the best habit
Salt, rinse aid, repairability and upkeep
Dishwasher salt is not optional: it regenerates the built-in water softener, which protects the element and the tub from limescale. Without it, in hard water, the appliance scales up and glasses become permanently clouded. The hardness setting must match the water in your area, information available from your water supplier.
All-in-one tablets contain small amounts of salt and rinse aid, which is enough in soft water but rarely in hard water. The doubt is settled by eye: white marks on glasses signal a lack of salt, dried droplets a lack of rinse aid.
The filter in the base of the tub lifts out, rinses and goes back in a minute. It is the most rewarding piece of maintenance there is: a clogged filter redeposits soiling on the load and gives the impression the machine washes badly.
Dishwashers fall under the French repairability index, displayed as a mark out of 10 next to the price. It aggregates available documentation, ease of dismantling, and the availability and price of spare parts. At comparable performance, it is a thoroughly concrete criterion.
Finally, check for an anti-flood device that shuts off the water supply in the event of a leak. It is a discreet feature whose value you measure only once, but forcefully.
- Dishwasher salt essential in hard water, hardness to be set
- White marks: salt missing. Dried droplets: rinse aid missing
- Rinse the tub filter regularly, the most useful maintenance there is
- Repairability index displayed out of 10, worth comparing
Frequently asked questions
Should crockery be rinsed before loading?
No, and it is actually counter-productive. Modern detergents need some soiling to work properly, and many appliances measure water turbidity to adjust the cycle: pre-rinsed crockery leads them to under-dose the wash. Simply scrape off large solid residues, without running items under the tap.
Does a dishwasher use more water than washing up by hand?
No, considerably less. An eco cycle uses only a few litres for a full load, whereas the equivalent washed by hand under a running tap takes several times as much. The gap widens further once you account for hot water, which costs more to produce than to circulate.
What does a dishwasher rated C or D mean?
That the scale has changed, not that the appliance is mediocre. Since March 2021 the rating runs from A to G, and the top classes were deliberately left empty to leave room for technical progress. Most appliances on the market now sit between C and E. Compare kWh per 100 cycles rather than letters.
Why do my glasses come out clouded?
Two possible causes. A white deposit that comes off with vinegar is limescale: the salt reservoir is empty or the hardness is set wrongly. A film that will not come off is glass corrosion, irreversible, encouraged by very soft water combined with high temperature. In that second case, lower the programme temperature and reduce the detergent dose.
Can plastic and cast iron go in the dishwasher?
Sturdy food-grade plastic goes in the upper basket, further from the element, and often comes out damp. Enamelled cast iron, sharp kitchen knives, bare aluminium, pewter and wood have no place in a machine: they dull, blunt or warp. When in doubt, look for the compatibility pictogram on the underside of the item.
Is 45 or 60 cm wide the better choice?
The 60 cm remains preferable wherever the kitchen allows, including for two people: running a large machine well filled every other day uses less than running a small one every day. The 45 cm is justified by a genuine space constraint, not by a wish to economise.
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