Why Your Dishwasher Isn't Drying Dishes Properly

Opening the dishwasher to find your plates and glasses still damp is frustrating, especially when the cycle has just finished and everything looked clean enough. The good news is that a dishwasher not drying dishes properly is often down to how drying actually works, rather than a fault with the machine. Once you understand the process, a few small habit changes usually sort it out.

Here we explain how condensation drying works, why leaving the door shut causes wet dishes, the part rinse aid plays, and when it's worth booking an engineer.

How dishwasher drying actually works

Most domestic dishwashers use what's known as condensation drying. There's no separate fan or heating element blasting hot air over your crockery. Instead, during the rinse and dry stage at the end of a programme, the machine heats everything up: the cabinet, the carcass, your glassware, ceramics and metal items.

It's the heat trapped inside all of those items that does the drying. As the load gradually cools, the moisture lifts away. The denser, more heat-retaining materials like ceramics, glass and metal hold that warmth well, which is why they tend to come out dry.

Why opening the door matters

This is the step most people miss. At the end of the cycle, the door should be left open slightly for a short time. Cracking it open lets the steam escape and allows the items to cool quickly, which is what finishes the drying process.

Leave the door shut for a long period and the opposite happens. The heat trapped inside the machine naturally cools and condenses back into water, so items that were on their way to dry end up wet again. If your dishes feel damp every time despite a hot wash, a closed door sitting for hours afterwards is the usual culprit.

Simple habits that fix poor drying

• Open the door at the end of the cycle. As soon as the programme finishes, pull the door open a little and let it stand for a short while before unloading.
• Avoid overnight or out-of-house cycles. If you run the dishwasher last thing at night or while you're out all day, the door stays closed long after the cycle ends and everything condenses back to wet. Try to run it when you'll be around to open the door afterwards.
• Check for an auto-open feature. Some higher end dishwashers have a mechanism that automatically opens the door a fraction at the end of a cycle to release steam. Many machines, though, rely on you to physically open the door, so don't assume yours does it for you.

Plastic items staying wet is normal

If your plates and glasses come out dry but the plastic tubs, lids and utensils are still wet, there's nothing wrong with your dishwasher. Plastic simply doesn't hold heat the way glass, ceramic and metal do, so it can't dry through condensation in the same way.

The plastic items will be perfectly clean, they'll just stay wet at the end of a cycle. A quick wipe with a tea towel is all that's needed.

The role of rinse aid in drying

Rinse aid is often overlooked, but it makes a real difference to drying results. It works by breaking down the surface tension of the water. Combined with the heat trapped inside the machine, this stops water clinging to your items and lets it run off in large sheets rather than sitting in droplets that dry as spots or stay wet.

It's always better to use rinse aid as a separate product rather than relying on an all-in-one combined tablet to do the job. A dedicated dispenser gives you proper control over how much is used and tends to deliver better drying.

How to top up the rinse aid

1. Open the dishwasher, lay the door flat and find the rinse aid dispenser on the back of the door.
2. Open the rinse aid cap and pour rinse aid into the compartment. You don't need to refill it constantly, as it isn't all used in one wash. A single top up can last several weeks or even months.
3. Wipe away any excess rinse aid from around the outside of the compartment with a cloth. Too much rinse aid in the machine causes oversudding, where far too much foam builds up.
4. Check that the water hardness setting on the machine is correct, as this controls how much rinse aid is dispensed.

Getting the balance right

The rinse aid setting matters more than you might think:

• Too much rinse aid leads to oversudding and excess foam inside the machine.
• Too little rinse aid leaves you with poor drying.
• The water hardness setting determines the amount dispensed, so set it to match your local water and you'll usually strike the right balance.

When to call an engineer

Work through the points above first. In most cases, opening the door at the end of the cycle, avoiding overnight runs, keeping the rinse aid topped up and checking the water hardness setting will clear up the wet dishes for good.

If you've done all of that and your dishwasher still isn't drying properly, there could be an underlying fault worth investigating. You can book a repair and one of our engineers will take a look. We quote a service charge before any visit that covers all callout, labour and VAT where applicable, and the only extra cost would be for any parts needed, which we'll always quote separately before carrying out the work. Repairs come with a guarantee under our terms and conditions.

Our engineers are trained across all the major makes, so whatever brand of dishwasher you own, we can help. You can also call us on 0333 016 9622 to talk it through, or check our service areas to see that we cover you.

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