Meaco 12L vs 20L dehumidifier: which size to buy?

What 12L and 20L actually mean

The litres a day figure is measured at warm, very humid test conditions, typically around 30 °C and 80 % relative humidity. In a UK home at 18 to 20 °C, both sizes will collect much less. What the rating does tell you is the unit's relative power: a 20 litre model can remove water faster than a 12 litre one in the same room. Our explainer on extraction ratings covers this in more detail.

Faster extraction matters most when there is a lot of moisture to deal with, such as a wet wash load, a steamy kitchen or a damp period after a leak.

Which size for which home

As a rough guide, a 12 litre unit suits a studio or one to two bedroom flat with ordinary condensation, or one bedroom or room in a larger home. A 20 litre unit suits a two to four bedroom house, a flat with heavy condensation, or anyone drying washing indoors several times a week. Our full size guide has a table by home size.

Noise, size and weight

Bigger units have bigger fans and coils, so they are usually larger and heavier. That matters if you plan to move it between rooms or carry it upstairs. Noise depends on the model and fan speed more than the size alone. Meaco quotes 38 dB for the Arete Two 20L, and the smaller models are listed in a similar range, so check the stated figure for the exact model. Our guide on dehumidifier noise levels explains what the numbers mean.

A larger unit can sometimes be quieter in practice, because it reaches the target humidity on a lower fan speed or in fewer hours.

Running hours and energy

A 20 litre unit draws more watts while running than a 12 litre one, but the humidistat switches it off once the room reaches the target. In a house with plenty of moisture, the bigger unit may hit the target in fewer hours, so the gap in kWh is often smaller than the wattage suggests. The Meaco Arete Two 20L is listed at 350 W; check the spec sheet for the 12 litre version you are considering, then use our running-cost calculator.

Arete One or Arete Two?

Within each size, the Arete Two adds features over the Arete One, such as the H13 HEPA filter and Wi-Fi app control on the 20 litre Arete Two. If you do not need app control or the purifier filter, the Arete One in the right size is the simpler choice. Our Arete One vs Arete Two comparison goes through the differences.

Compare the best 20 litre dehumidifiers →

Our recommendation

If you are unsure, size up. A 20 litre unit in a smaller home will simply run less, while a 12 litre unit in a large or very damp home may run constantly and still fall short. Buy the 12 litre size when space, weight or one-room use make the larger unit impractical. For other brands in the larger size, see our guide to the best 20 litre dehumidifiers.

Frequently asked questions

Is a 12L dehumidifier enough for a house? For a small house with mild condensation it can be, but a three or four bedroom house or regular laundry drying usually calls for a 20 litre unit.

Does a 20L Meaco use much more electricity? It draws more watts while running, but it often reaches the target humidity sooner and then switches off, so the daily kWh difference can be modest.

Will a 20L unit really collect 20 litres a day? No. That is a rating at warm, very humid test conditions. In a heated UK home it will collect much less.