Dishwashers

Dimensions

• Size: A lot of 12- to 15-place models fit roughly the same-sized under bench space (82-85cm height, 60cm width and 55cm to 65cm depth). If you are replacing an existing dishwasher, check the fit before you order. Some models come with a worktop that must be removed before building in. Check the ventilation space requirements. If you’re looking for a dishwasher to squeeze into a small space, a compact or slimline model might be right for you.

• Capacity: The dishwashers in our test database come in sizes up to 15 place settings. Overfilling a dishwasher with extra crockery and cutlery reduces wash performance.

Flexible loading

• Adjustable top basket: Essential if you want to wash champagne flutes or other tall wine glasses, or wash very large plates in the lower basket. Some models let you lower one side of the basket, so you can wash tall glasses and large plates at the same time.
  Removable or folding tines allow large or awkwardly shaped objects to fit in the baskets. Watch out for short tines – plates can fall over onto each other and prevent a good wash.
  Take along a few pieces of your everyday dinnerware such as a large plate, a deep bowl and a long-stemmed glass. See how they fit – check that the baskets can close and the spray arms can spin without hitting anything.

• Anti-nesting grids: Fitted over the cutlery basket to prevent cutlery bunching together. Removable grids are more versatile and easier to use.

• Cutlery tray: Here's an innovation in some models you'll either love or hate. Critics find it time consuming and fiddly to load, because each piece of cutlery has to go in its own slot – the right way round. And it can prevent tall glasses from fitting, unless the tray is removed.
  Our test found there was no performance advantage with a cutlery tray. A basket may be offered as an alternative or in addition to a tray.

Settings

• Program options and features: What do you want your dishwasher to do? The options vary. A low temperature wash saves power, and lets you take advantage of the new enzyme detergents. A delicate cycle is useful for fragile items. A fast-wash function is efficient if you've pre-rinsed the plates to remove the worst of the grime. A half-load option reduces the amount of detergent, power and water required.
• Cycle time: A normal cycle takes around 2 to 2.5 hours. Some models have a fast cycle, and those with a hot connection will be quicker than those which heat the water themselves.
• Auto-sensing: An auto-sensing feature allows a dishwasher to analyse the water and assess how dirty your dishes are. It then adjusts water temperature and the length of time to suit. However, not all dishwashers are good at auto-sensing. As part of our test, we assess a dishwasher’s auto-sensing feature.
• Displays: It's helpful to see how soon the cycle will finish, or where to look to fix simple problems, such as blocked spray arms.
  

Other features

Additional features to consider when you're choosing a dishwasher.

• Anti-flooding devices: Worth having. Often fitted to the hose, to prevent your kitchen becoming awash if there's a leak.
• Concealed heaters: We can't see any difference in performance, though stray plastic items are more likely to melt onto an exposed element. If you must wash plastic, do larger pieces only, and in the top rack.
• Noise: If you're used to a 15-year-old dishwasher, you'll probably be astonished at how quiet the current models are. Machines that can wash at levels below 45dBA won't intrude too much on your post-dinner chat.
• Style: The right look can be a key factor. Most brands offer stainless steel and integrated options. Integrated models (often with an "i" in the model number) can be fitted with a front panel to match your kitchen décor.
• Child proofing: Door locks, and child-safe detergent dispensers could prevent accidents.
• Filter: Make sure the filter is easy to remove and replace.
• Controls: Look for clearly labelled buttons and a display screen or rotary dial to indicate time remaining.

Most dishwashers come with a single water connection, and manufacturers usually recommend you hook it up to cold water.

You might be tempted to save money by connecting to your hot water if it comes from a wetback, heat pump or solar unit. But before you do that check the maximum water-inlet temperature (see the test results). Also make sure you have a suitable tempering valve on your hot-water system.

If you have a standard electric hot-water cylinder, allowing your dishwasher to heat its own water will be fractionally cheaper than using the cylinder’s.

Using a cold connection also gives you the full flexibility of all the cycle options on your machine.

Unless you really must, we think new is better. But if second-hand is your only option:

• Stick to well-known, reliable brands under 5 years old. It'll be easier to get parts if anything needs fixing. See our reliability data for brands to look for.
• Check the door seal is intact and that the door clicks shut properly.
• Check all connecting and drainage hoses are intact and in good condition.
• Make sure the inside is free from rust, the filter is clean, and the baskets slide in and out easily.
• Under the Electricity Act and its regulations, electrical appliances for sale must be safe. This law applies to every way of selling an electrical appliance, new or used.
• If you buy a dishwasher from a second-hand dealer and then discover it to be faulty, you're covered by the Consumer Guarantees Act. If you buy privately, you're not.

It's hard to work out how old a dishwasher might be. It's also not easy to find out how much water and energy an older model uses.

The Energy Rating Label has a scale of stars to show how energy efficient a model is, compared to other models of the same size/capacity.

More stars = more energy efficient.

The energy consumption figure is in kilowatt-hours (kWh) and you can use this figure and the cost (tariff) from your latest power bill to calculate how much this model will cost to run. The MBIE-reported national average cost of a kWh in New Zealand is 29¢.

Lower kWh = cheaper to run.

Dishwasher annual energy consumption in kWh is based on standards testing and assumes 365 uses a year.

You should only compare star ratings of dishwashers with the same or similar capacities.

For information on energy ratings and how to use them, see our Energy Rating Labels explained article.