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Powerful, flexible and with loads of space inside, the Whirlpool WIO 3O33 DEL is the only dishwasher that you need for less than £650. Its 6th Sense technology is brilliant, adjusting water and wash times based on how dirty your dishes are. This is one of the few machines that we’ve tested that deliver almost perfect washing results across all of our tests.


  • Excellent cleaning results
  • Brilliant PowerClean feature
  • Super-frugal with water and electricity
  • Good selection of programmes
  • Effective 1-hour wash & dry
  • Very quiet


  • Powerclean heavier on electricity
  • Cutlery tray not removable
  • No interior light

What is the Whirpool WIO 3O33 DEL?

Integrated dishwashers have often played second fiddle to their freestanding counterparts, with limited space, fewer features and so-so eco efficiencies. Whirlpool turns that concept completely on its head with the A+++-rated, fully featured, large capacity WIO 3O33 DEL built-in dishwasher.

Incredibly energy efficient, with the additional turbo-boost of Whirlpool’s PowerClean for really mucky dishes and pans, outstanding racking space and brilliant cleaning make this a fabulous dishwasher for kitchens with built-in appliances. Are we impressed? Welcome to TrustedReviews’ first ever 10/10 dishwasher!

Related: Best Dishwashers

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Whirlpool WIO 3O33 DEL – What’s it like to use?

We’ve been impressed by some of Whirlpool’s more recent freestanding dishwashers. They’ve washed well, been energy efficient, and the internal flexibility has been among the best. Their PowerClean and PowerDry features have worked a treat – albeit with the use of a bit more electricity. Can Whirlpool replicate this success in a built-in model?

The WIO 3O33 is the company’s flagship integrated dishwasher, available for the not-inconsiderable sum of almost £650. Yet this isn’t deemed expensive for a built-in appliance – models designed to sit sleekly within a kitchen carcass have always come at a significant premium over their freestanding counterparts.

Part of Whirlpool’s Supreme Clean series, this model features the brand’s 6th Sense technology, which senses how dirty the load is and adjusts water consumption and wash duration accordingly. It also has a PowerClean option – pushing high-pressure water through additional jets in the base – and PowerDry as standard.

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PowerClean is designed for very dirty cooking pots and pans, but is just as effective on plates with dried-on foods. PowerDry runs as standard on most programmes and incorporates a fan that draws moist air from the interior, rather than letting water slowly evaporate in the heat. PowerDry dramatically speeds up drying times and allows the WIO 3O33 to boast a super-speedy one-hour Wash-and-Dry programme.

The interior compartment leverages just about every clever dishwasher racking and stacking feature we’ve seen. The lower basket rolls out with ease, is of a good depth, and features two double-tine rows of plate racks. Each row is divided in two sections – longer and shorter – and every part can be collapsed flat if required. This provides plenty of flexibility, from a completely flat basket for lots of pots and pans to completely racked out for plates. There are several options in between for mixed loads.

At the rear of the lower basket are two flip-down supports. When lowered, these support pots and pans so they directly face the rear PowerClean jets. They also ensure larger items can be placed upright, saving space even if you’re not using the PowerClean feature.

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The upper basket is just as flexible. It features a complete row of double-tine plate racks, split just over half way with smaller and slightly larger tines. Ideal for saucers and small plates, the tines can be all or partly folded flat, providing more space for bulkier items such as cups and bowls. You also get four pull-down glass/cup racks, each with two height positions.

If you need to make some extra room down below for larger plates, the upper basket can be raised up about 3.5cm on each side. You can raise just one side if that works best for the load. If you raise both, the lower basket can then handle plates of up to 27cm across – that’s 1cm bigger than our tallest test-plate.

At the very top is a shallow cutlery tray with some outstanding features. Its racking is designed so that cutlery stands on its edge for extra space, and the tray is in four pieces that slide left to right and over each other. This allows you to shrink the tray down to two-thirds of its full width, and position it to the left or right side of the cabinet.

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The upshot is that if you have very tall wine glasses or cups on top of the upper basket’s cup-racks, you can slide the cutlery tray out of the way. Placed in the middle, the truncated tray even affords you a little space on both sides. Our only complaint with the cutlery tray is that you can’t remove it to take it directly to your cutlery drawer for easy unloading.

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Salt, rinse aid and the detergent compartments are all standard affairs, as is the pinch-to-remove filter basket in the base. Like all integrated dishwashers, real estate for the controls and display is limited to the top edge of the door.

Here, Whirlpool has fitted a bright white display with red warning symbols and solid-feeling stainless steel buttons for programme selection and options. Programmes are listed as symbols along this top edge, but in very fine print that had us reaching for the reading glasses.

Start/Pause is achieved by simply closing the door; a yellow light at the bottom of the machine flashes slowly onto the floor to indicate when the dish washing has finished. We’d have liked an interior light just to see what we were doing on dull days, but that’s really being picky.

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Whirpool WIO 3O33 DEL – What programmes does it have?

This model has 10 programmes and a Self-Clean cycle, with the list headed up by the Eco 50 wash. This is the default programme for the energy label testing, so leverages a lot of soak time to reduce energy consumption.

This cycle is fixed at a 3hrs 40mins duration and 50oC for normal loads. You can also engage the PowerClean option, but since this uses more electricity, it would seem counter-intuitive on this Eco cycle.

The hero programme is Whirlpool’s 6th Sense wash, and we reckon this will be your go-to cycle. It senses the level of soiling on the dishes by measuring the turbidity of the water at each phase, and adjusts temperature and wash duration accordingly.

You can add in the PowerClean option, choose to wash any one of the three baskets individually, or use the delay timer up to 12 hours. Durations and energy consumption will vary on how dirty your wash is, but expect this cycle to run anywhere from an hour and a half to 3 hours.

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The 1 Hour Wash & Dry programme is likely to be a big hit with busy families, and is ideal for lightly soiled loads comprising mainly plates, crockery and cutlery. Whirlpool’s forced-air PowerDry feature really speeds up drying time; we found this cycle very effective considering its super-speedy wash time.

You get a Rapid 30 half-hour wash if you’re happy to tea-towel dry the load, an Intensive 65oC cycle for really messy saucepans and frying pans, and a Crystal 45oC wash ideal for glassware.

There are two programmes we struggle to think of a good use for: the Daily 50oC programme, which does the same as 6th Sense cycle but without the sensing, and the Silent 50 cycle. Since this Whirlpool is super-quiet, even with the PowerClean option running, we’re not sure why you’d need an even quieter programme.

The programme list is complete with a 12-minute pre-wash programme that quickly sluices the load to stop food drying on your plates – handy if you’re going to run the dishwasher later on. There’s also a 65oC sanitizing wash to aid the elimination of bacteria.

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Whirlpool WIO 3O33 DEL – How noisy is it?

Our real-world tests show that dishwashers always make a fair bit more noise than the energy label suggests. Also, we test integrated dishwashers in an open kitchen carcass without a furniture door attached, so our integrated results will always be a little higher than what you’ll experience when the machine is properly installed. But the WIO 3O33 is unbelievably quite from the outset.

Proving to be comfortably one of the quietest dishwashers we’ve ever tested, integrated or freestanding, we measured just 44dB on standard programmes. That is a super-quiet, library-standard hush for a dishwasher, and is likely to be a couple of decibels quieter still when installed into a built-in kitchen unit.

Most of the noise from a dishwasher is the sound of water splashing around your dishes and pans, so it was no surprise to find that engaging the PowerClean feature and its high-pressure water jets increased the noise.

However, the wash noise only went up to a still amazingly quiet 49dB. That’s an absolutely outstanding result, ensuring this Whirlpool is one of the quietest dishwashers on the market – irrespective of what programmes or features you use.

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Whirlpool WIO 3O33 DEL – How well does it wash?

In the first full-load test, we loaded the WIO 3O33 up to the max with a mix of plates, crockey, glassware, cutlery and assorted kitchen utensils. In this first wash we also placed a couple of over-size wine glasses with red-wine residue, plates with dried-on baked beans, a breakfast bowl with Weetabix leftovers and a Pyrex bowl that had been used to cook cheesy scrambled eggs in the microwave.

For good measure, we left the load in the dishwasher for a day so that the stains could dry on solid before running the test. We opened the batting with the Eco 50 programme as a standard to benchmark against other machines, and left the PowerClean feature switched off.

Nearly four hours later and the yellow flashing light on the floor indicated the wash was complete.

Opening the door we could immediately see that drying results were truly outstanding – Whirlpool’s PowerDry had worked its magic. There was barely a spot of moisture left on any of the wash items, and even the interior walls of the dishwasher were dry. There were some very small pools left on the concave bases of cups we’d specifically placed flat, but that would have been eliminated had we place them correctly on the sloping racks.

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The wine glasses certainly benefited from this excellent drying; they were spotless, streak-free and ready to go straight back in the cupboard as they were. The breakfast plates and Weetabix bowls were equally pristine and nicely dry.

But it was the scrambled egg bowl that impressed most. This was extremely well addressed with only a few, tiny remnants of scrambled egg stuck to the glass – an excellent result for this usually “impossible” test.

We immediately wondered what the PowerClean might achieve, and ran the whole test again (having to drink more red wine in the name of science… ) with the option selected. While the energy use figures went a little skyward, there certainly was no denying the superb cleaning power of this option.

The WIO 3O33 joins a very small and exclusive set of dishwashers that cleaned our scrambled egg bowl almost perfectly. There was no hint of egg left on the glass and only the faintest smear at the very base of the bowl – which doesn’t even show in the after photograph. This required only the lightest of buffs with a tea towel as we put the bowl away. A truly outstanding cleaning result – and class-leading among the integrated models we’ve tested.

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Whirlpool WIO 3O33 DEL – How much does it cost to run?

All this cleaning power and A+++ energy efficiency are unlikely bedfellows, but this Whirlpool does an equally outstanding job of balancing the two.

Our first standard full load on Eco mode used just over 1kW of electricity and just 9 litres of water. The electricity is a little higher than suggested by Whirlpool’s own figures, but tested in mid-winter our incoming water temperature was a chilly 8oC. In more regular weather with water closer to 13-15oC, the energy figure will be down to around 0.8-0.9kW.

Unfortunately, engaging the PowerClean feature does blow the A+++ energy efficiency right out of the dirty dishwasher water. The same Eco 50 programme with PowerClean engaged more than doubled the energy used to 2.2kW and added another litre of water.

However, since this is an optional feature, and only likely to be used for really tough cleaning jobs, this is more than acceptable energy use for its amazing cleaning prowess in our opinion.

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Besides, if you want really frugal then go for this Whirlpool’s 6th Sense programme. We rewashed the main load with only very light day-to-day soiling on the 6th Sense programme and had to do it three times because we didn’t actually believe our own results.

Not only was the cleaning and drying very good, this lightly spoiled load required just 0.9kW of energy and a stupendously low 5 litres of water. We got 5 litres the second time and then ran the cycle with a clean load to see what the 6th Sense would make of that. In this wash it used just 4 litres of water. I think I drank more tea than that during testing!

For normally soiled loads Whirlpool suggests around 7 litres – which is far less water than you’re likely to use washing a whole dishwasher full of crockery in the sink.

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So, based on running 250 dishwashing cycles per year, half on the Eco 50 programme for normal loads and half on 6th Sense for more mixed-soil loads, the WIO 3O33 would comfortably use less than £40 in electricity for the year. Obviously, that will go up with the PowerClean option, but only by around 15-20p per load. If your pots, pans and dishes are that messy, we reckon that the Whirlpool’s superb cleaning makes that 20p well spent.

Since this machine sips water, your annual bill is unlikely to be hit hard by our calculated 2.5 cubic meters of water use per year either. If you’re on metered water, at an average of £3.50 per cubic meter of supply and waste, the WIO 3O33 DEL would add less than £10 a year to your water bill. That makes this fabulous dishwasher one of the most frugal we have ever tested – integrated or freestanding.

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Should I buy the Whirlpool WIO 3O33 DEL?

We don’t fall in love with too many domestic appliances, but every now and again, a model comes along that is truly outstanding. The Whirlpool WIO 3O33 DEL dishwasher is just such an appliance, boasting fantastic cleaning power at super-quiet noise levels, amazingly flexible interior space and very low running costs.

Given that it isn’t even as expensive as many top-end freestanding dishwashers, but performs equally as well and offers fully integrated style, the WIO 3O33 is a built-in bargain.

A truly class-leading integrated dishwasher that offers outstanding cleaning, superb flexibility and low running costs.

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