Compressor vs desiccant dehumidifier: which do you need?

The two types side by side

The power, extraction and noise rows are averages across the 6 compressor and 3 desiccant models we list, from their rated specs. The extraction figures aren't like for like: most compressor figures are measured at 30°C and 80% humidity and the desiccant ones at 20°C and 60%, so in a heated home the real gap is smaller than the table suggests.

	Compressor	Desiccant
How it dries the air	Draws air over cold coils so the water condenses	An absorbent wheel soaks up the water; a heater dries the wheel
Average power	297W, 7.8p an hour	633W, 17p an hour
Average extraction	17 litres a day	8 litres a day
Below about 15°C	Slows right down and spends time defrosting. Lowest rated temperature in our list: 5°C	Keeps working. Lowest rated temperature in our list: 1°C
Average noise rating	40dB	39dB
Heat output	Warms the room very slightly	Warms the room a little
Weight	Heavier, because of the compressor	Lighter and easier to carry between rooms

On noise: about the same in our list, so choose on the other rows and then compare noise model by model.

How each type works

A compressor dehumidifier works like a small fridge. A fan draws room air over coils that are colder than the air's dew point, water condenses on them and drips into the tank. It needs the coils to be much colder than the room. In a cold room the gap shrinks, less water condenses, and the coils can ice over, so the machine stops to defrost.

A desiccant dehumidifier passes the air through a slowly turning wheel of absorbent material. A heater then drives the water back out of the wheel so it can be collected. Because it doesn't rely on cold coils, it works much the same in a cold room as a warm one. The heater is where most of its power goes, and that heat ends up in the room.

Which one suits your home

A heated house or flat: compressor. A room with the heating on is usually warm enough for it, and it costs much less to run.
A garage, shed, conservatory or a room you never heat: desiccant. See dehumidifiers for garages and cold rooms.
A cold bedroom you keep the heating off in: desiccant. The slight warmth is useful there, and it keeps drying when a compressor model would struggle.
Drying washing in a heated room: compressor with a laundry mode. See dehumidifiers for drying laundry.
Carrying it up and down stairs: a desiccant model is usually the lighter of the two.

Running costs

Desiccant models draw more power. Run for six hours a day, the compressor pick below costs about 32p a day, and the desiccant pick about £1.03. Both have a humidistat, so once the room reaches the humidity you set they cut back and the real cost drops.

In a cold room the gap matters less than it looks. The desiccant model's heat warms the room, and it keeps collecting water when a compressor model would be defrosting. In a heated home, a compressor model does the same job for less. Compare every model on the running costs table.

Costs use 26.32p per kWh, the Ofgem price cap, Direct Debit average for England, Scotland and Wales for 1 October to 31 December 2026. Your own tariff may differ. How we calculate.

Dehumidifier size calculator Tell it how warm the room is in winter and it picks the type and size for you.

Our picks

One of each type, chosen by their specs. We haven't tested them ourselves; the reasons say which spec puts each one here.

Compressor, for a heated home

Pro Breeze OmniDry 12L

Type: Compressor
Extraction: 12 litres a day
Power: 200W
Noise: 36dB
Tank: 2 litres
Cost per hour: 5.3p

Laundry mode

12 litres a day at 200W, a 2 litre tank and a 36dB noise rating, which is low for its size. It has a laundry mode too, at 5.3p an hour.

View on Amazon Manufacturer specs

Desiccant, for a cold room

Meaco DD8L

Type: Desiccant
Extraction: 7.5 litres a day
Power: 650W
Noise: 39dB
Tank: 2 litres
Cost per hour: 17p

Laundry mode

Rated to work down to 1°C, with 7.5 litres a day and a 39dB rating. It costs more to run, at 17p an hour, but keeps drying in a room a compressor model can't cope with.