A heat pump dryer dries your laundry with air it uses over and over. Instead of blowing warm air outside, it takes the moisture out and reheats that same air. That saves roughly half the electricity compared with an old vented dryer, and it is why almost every dryer sold today is a heat pump model.
This article covers how the technology works, the difference with a condenser dryer, what a heat pump dryer asks of your space, and what to look for when choosing one.
How a heat pump dryer works
In an ordinary dryer, air is heated, blown through the drum and then thrown away: through a hose to the outside, or into a reservoir after cooling. All the heat you put in is gone.
A heat pump dryer does it differently. The moist air from the drum passes a cold evaporator, where the moisture condenses and runs into a reservoir. That same air then passes a warm condenser, where it is heated again, and goes back into the drum. The heat pump moves heat around rather than generating it over and over.
Two consequences are noticeable. The dryer uses considerably less power, and it dries at a lower temperature. That last point is kind to your clothes: less shrinkage and less wear. It also means a cycle takes longer than you may be used to, often two to three hours.
Heat pump or condenser: what is the difference?
This causes a lot of confusion, and rightly so, because the answer is: a heat pump dryer is a condenser dryer. Both take the moisture out of the air and collect it in a reservoir; neither needs a hose to the outside.
The difference is in how they heat the air. A classic condenser dryer uses an electric heating element and cools the moist air with room air. A heat pump dryer uses a heat pump and reuses the heat. So searching for a condenser dryer means searching the category heat pump dryers also belong to, but in its most efficient form.
The third type, the vented dryer, blows the moist air outside through a hose. It needs a wall duct or an open window, and uses the most power. New ones are barely sold any more.
What the label does and does not tell you
The energy label for dryers is strict. A heat pump does not automatically mean an A. Our dryers sit in classes C, D and E, using 220 to 259 kWh a year. For comparison: a ten year old vented dryer easily reaches 500 kWh.
So look beyond the letter at the kWh per year figure, because that is what your electricity bill responds to. At around 160 cycles a year and a rate of 30 cents per kWh, 220 kWh works out at some 66 euros a year, or a little over 40 cents a cycle.
What a heat pump dryer asks of your space
The condensate has to go somewhere
By default the collected water goes into a reservoir you empty every few cycles. Forget it and the dryer stops. Almost all models can also drain directly through a hose to a floor drain or your washing machine's trap, and then you never have to empty anything. That is a matter of connecting a hose, not plumbing.
It needs room and air
A heat pump dryer cools itself with the air in the room. Put it in a closed cupboard without ventilation and that air keeps getting warmer, slowing the drying. In a shed that drops below five degrees in winter it also performs poorly. An ordinary utility room or bathroom is fine.
On or beside the washing machine
If you want it on top of the washing machine, always use a stacking kit. Without one the dryer walks off the machine as soon as it spins. A kit with a pull-out shelf is handy if the dryer ends up above eye level.
Which capacity do you need?
Wet laundry takes up more room than dry, but your dryer does not have to be as large as your washing machine. The rule of thumb is about two thirds: a 9 kg washing machine pairs comfortably with an 8 kg dryer, and 10 kg with a 9 kg dryer.
Go smaller and you split a full load over two drying cycles and spend longer at it. Go larger than needed and you pay for space that stays empty, while a half-full drum dries less efficiently.
Maintenance: two filters and a condenser
A heat pump dryer asks a little more attention than an ordinary one, and that is exactly where things often go wrong. Two things need doing regularly.
The lint filter in the door should be cleaned after every cycle. That is ten seconds of work and it is the most important habit: a full filter slows the dryer and raises consumption directly.
The condenser filter, usually behind a flap at the bottom, should be rinsed out every few months. Models with a self-cleaning condenser do not need this, but check it once a year anyway. A blocked condenser is the most common reason a dryer stops drying properly.
What else to look for
Noise. A heat pump dryer makes a humming sound from the compressor. If it sits next to the living room, check the stated decibel figure.
Anti-crease function. If the drum keeps turning occasionally after the cycle, your laundry stays loose, which saves ironing when you do not take it out straight away.
Time remaining and delayed start. Useful if you run on an off-peak tariff or want the laundry ready when you get home.
Door hinge side. If the dryer stands in a corner, check that the door opens the right way; on some models this can be swapped.
Our heat pump dryers
Every tumble dryer in our range is a heat pump model, from Heinner and Fram, in capacities from 7 to 10 kg. They are delivered and installed free of charge, with a five year warranty. Unsure about the size? Look at your largest wash rather than your average one.
Veelgestelde vragen
Is a heat pump dryer the same as a condenser dryer?
A heat pump dryer is a type of condenser dryer. Both take the moisture out of the air and collect it in a reservoir, and neither needs a hose to the outside. The difference is that a heat pump dryer reuses the warm air instead of heating it again, and so uses roughly half the electricity.
Why does a heat pump dryer not have energy class A?
The energy label for dryers is strict, and a heat pump alone is not enough for the top class. Our dryers sit in classes C, D and E, using 220 to 259 kWh a year. So look at that kWh figure too: a ten year old vented dryer easily reaches 500 kWh a year, which means even a class D heat pump dryer halves your consumption.
How long does a cycle take with a heat pump dryer?
Expect two to three hours for a full drum. That is longer than with an old dryer, because a heat pump dryer works at a lower temperature. That is exactly what makes it efficient and what spares your clothes: less shrinkage and less wear.
Do I have to keep emptying the water reservoir?
Not if you let it drain. Almost all models can send the condensate straight out through a hose to a floor drain or your washing machine's trap. Without that connection you empty the reservoir every few cycles; if you do not, the dryer stops by itself.
Can a heat pump dryer stand in a shed or garage?
It can, but it performs poorly in the cold. A heat pump dryer uses the surrounding air to cool itself, and below about five degrees the drying time rises sharply. In a heated utility room, back kitchen or bathroom it performs best. Also avoid closed cupboards without ventilation.
Which dryer suits my washing machine?
Reckon on about two thirds of your washing machine's capacity, because wet laundry takes up more room. A 9 kg washing machine pairs with an 8 kg dryer, and 10 kg with a 9 kg dryer. Smaller is possible, but then you split a full load over two cycles.
