5 things I’d never do as a tumble dryer expert

Some tumble dryers can be expensive to run, but by loading it properly and keeping on top of basic maintenance, your appliance will perform more efficiently and last longer.

As a tumble dryer expert, here are five things I'd never do when dealing with dryers.

Discover how the best tumble dryers performed in our rigorous lab tests

1. Let the lint filter get clogged up

The lint filter on a tumble dryer is designed to trap any stray fibres from clothes which could clog up the vent hose.

A clogged filter will prevent air from circulating properly, meaning your clothes won't dry as efficiently. This can mean you're tumble drying for longer than you need to, making your machine more expensive to run.

Lint build-up is also flammable, and can cause an increase in temperature in your machine. Tumble dryers come with a thermal cut-off, so the machine will be designed to stop working when it gets too hot inside the drum. 

We'd advise clearing the lint filter after every use to keep your dryer running smoothly and safely. Familiarise yourself with tumble dryer safety to help avoid any accidents.

2. Ignore the heat exchanger on a condenser dryer 

A condenser dryer works slightly differently to a vented dryer. Instead of heated air drying the clothes and being expelled as steam, a heat exchanger condenses the warm air from the wet clothes into water, which is then collected in a reservoir under the machine.

Much like a lint filter, the heat exchanger can get clogged up. The heat exchanger is a small, shoebox-sized plastic and metal device at the front of the machine. Once removed, you can clean away the fluff by hand or under a tap. Try to clean it once a month – check the manual or visit the manufacturer's website for instructions. 

The same goes for the lower filter on a heat pump dryer, which comes in two parts. The front filter is a sponge that can be removed and rinsed under the tap. Behind it is the heat exchange unit or evaporator. Unlike the unit on a condenser dryer, this can't be removed, so it needs to be gently brushed clean every now and then. 

Discover more tumble dryer cleaning and maintenance tips for vented, condenser and heat pump models 

3. Run an overfilled (or half-empty) dryer 

To dry clothes effectively, tumble dryers need to be able to circulate hot air freely within the drum. Overfilling means that drying takes much longer, the quality of the drying will be reduced (you might find a damp sock lurking), and too much heat could build up in the drum.

That being said, running a mostly empty dryer isn't particularly cost-effective either. If you've only got one or two items to dry, hanging them up outside or on something like a heated airer instead is a much better option. Find out how a dehumidifier can also help get your laundry dry indoors.

Discover 10 ways to cut the cost of tumble drying

4. Put wool in a tumble dryer

Our general advice is to avoid using a tumble dryer when drying wool because the temperatures reached in the drum are simply too high. Heat from the tumble dryer causes the fibres to interlock, making the fabric tighter and smaller. 

This is especially true of vented or condenser tumble dryers, where drum temperatures will be significantly higher than with heat pump machines. 

Our tests show that, every now and then, a dryer comes along that can gently dry woollens without shrinking them, but they’re few and far between. You're better off air-drying your woollen garments to keep them looking their best.

Find out what happened when we put woolly jumpers in a no-shrinkage guarantee tumble dryer 

5. Buy a tumble dryer based on price alone

When shopping for a new tumble dryer, consider more than just the upfront cost. You'll need to think about the running costs, size, the features you'll need, and how frequently you'll use it.

Vented and condenser dryers are usually cheaper to buy, but the running costs tend to be high.

Instead, an energy-efficient heat pump tumble dryer might cost you slightly more upfront, but uses less than half the energy of a vented or condenser dryer, so it'll work out cheaper in the long run.

Find out how much it costs to run a tumble dryer

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