Compressor or desiccant dehumidifier: which is right for you
If the room is above about 15 °C, a compressor dehumidifier removes more water for less electricity. In a cold bedroom, a garage, a conservatory or an unheated home — common in a British winter — a desiccant works much better.
Quick verdict
- Buy a compressor model if… you will use it in a heated home, in rooms above 15 °C. It removes the most water per kWh and is the cheapest to run.
- Buy a desiccant model if… the room is cold (below 15 °C): bedrooms with the heating off at night, garages, conservatories, cellars or a holiday let. It also gives off some warmth and is lighter.
- Before you buy either… open a window for ten minutes a day, use the extractor fan when cooking and showering, and do not dry washing indoors without ventilation. Sometimes that alone brings humidity down from 70% to 60%.
Compressor vs desiccant dehumidifier at a glance
| Small compressor (10–12 L/day) | Large compressor (16–25 L/day) | Desiccant (7–10 L/day) | |
|---|---|---|---|
| Best temperature | Above 15 °C | Above 15 °C | 1 to 25 °C |
| Power | 150–250 W | 250–450 W | 300–700 W |
| Electricity for 8 hours (≈ 25p/kWh) | 30–50p | 50–90p | 60p–£1.40 |
| Real extraction in a cold room (10 °C) | Very little | Little | Close to the label |
| Noise | 38–45 dB | 42–50 dB | 35–45 dB |
| Weight | 10–13 kg | 13–18 kg | 6–8 kg |
| Warms the room | Slightly | Slightly | Yes, by 1–2 °C |
| Price | £120–£200 | £180–£320 | £130–£230 |
Indicative UK prices as of November 2026. Running costs use about 25p/kWh, close to the Ofgem price cap. Note: compressor litres per day are measured at 30 °C and 80% humidity; in winter they remove far less.
How each one works (and why temperature matters)
A compressor dehumidifier works like a fridge: it chills a coil and the water vapour in the air condenses on it. The colder the air, the less water condenses, and below about 15 °C it performs much worse; in a room at 10 °C it can remove a fraction of what the box says.
A desiccant dehumidifier passes the air through a wheel of moisture-absorbing material (zeolite) and dries it with a heater. It does not depend on temperature, so in a cold room it removes almost as much as in a warm one.
Think about the temperature you will use it at, not just the litres per day. It is the difference you notice most in winter.
What each one costs to run
A small 200 W compressor model running eight hours a day uses 1.6 kWh: about 40p a day, or roughly £12 a month. A 600 W desiccant used the same way uses 4.8 kWh: about £1.20 a day, or around £36 a month.
A desiccant gives almost all of that energy back as heat, so in a cold room it is not all wasted: it warms it by a degree or two. In a home that is already heated, a compressor model is clearly cheaper.
Both have a humidistat: set it to 50–55% and it switches off by itself once it gets there, so in practice they use a lot less than running non-stop.
Which home suits each one
- A heated flat or house kept above 15 °C: compressor. It performs well and is cheap to run.
- Bedrooms that stay cold, with the heating off overnight: desiccant.
- Garage, conservatory, cellar or workshop: desiccant. Compressor models can ice up their coil and stop.
- A holiday home or let left closed in winter: desiccant, with continuous drainage.
- Drying washing indoors: either with a laundry mode; a desiccant also helps with its warmth.
What humidity to aim for, and when to worry
Comfortable and healthy is between 40% and 60% relative humidity. Above 70% for long periods you get condensation on windows, a musty smell and, over time, mould in corners and behind furniture.
A £10 digital hygrometer tells you whether you really have a problem before you spend on a dehumidifier. If mould keeps coming back even with lower humidity, there may be a leak, rising damp or a cold spot: that needs a professional, not an appliance.
What to look for when buying
- Real capacity: for a two- or three-bedroom home, 10–12 L/day (compressor) or 7–8 L/day (desiccant) is usually enough.
- An adjustable humidistat and a display showing the current humidity.
- A 2–3 litre tank with a full alert and auto shut-off, and a hose outlet if you do not want to empty it.
- Laundry and night modes (low fan, lights off).
- Wheels and a handle: compressor models weigh over 10 kg.
- A washable filter and, on compressor models, auto-defrost if you will use it near 15 °C.
Where to buy
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Meaco Arete One 10L dehumidifier
A quiet, efficient 10 L/day compressor model from a UK specialist, with laundry mode and a built-in air purifier filter.
Pro Breeze 12L compressor dehumidifier
Good value 12 L/day model with humidistat, laundry mode and continuous drainage.
Meaco DD8L Zambezi
The reference desiccant: 8 L/day that holds up in the cold, quiet, light and with laundry mode.
EcoAir DD122 desiccant dehumidifier
A popular, light desiccant for cold bedrooms, garages and conservatories.
Digital hygrometer thermometer
To see the real humidity in each room and whether you need a dehumidifier at all.
Frequently asked questions
Which dehumidifier is best for a cold room?
A desiccant. Compressor models lose a lot of performance below about 15 °C, while a desiccant removes almost as much water at 5 °C as at 20 °C.
How much does a dehumidifier cost to run?
A 200 W compressor model running eight hours a day costs around £12 a month at 25p/kWh. A 600 W desiccant costs around £36, although it also warms the room a little. With the humidistat set properly, both cost less.
What humidity should my home be?
Between 40% and 60%. Above 70% for long periods you get condensation, a musty smell and mould.
Does a dehumidifier get rid of mould?
It stops it coming back by keeping humidity down, but it does not remove it: you still need to clean it off. If it returns even with good humidity, look for a leak or a cold wall.
Can a dehumidifier dry washing?
Yes, and far better than just hanging it up indoors. Put the washing in a closed room with the dehumidifier on laundry mode: it dries in a few hours without filling the house with damp.