1 / 6CosmartAir BW406 Dehumidifier, 3,000 ml Tank
CosmartAir BW406 is a compact dehumidifier with a listed 3,000 ml tank, timer, sleep mode and colour lighting. The listing also claims up to 750 ml/day collection under specified conditions, automatic tank-full shut-off and a 640-square-foot coverage area, so check that the stated capacity suits the room and your expectations.
At a glance
- The listing claims a 3,000 ml transparent tank with automatic shut-off and an LED alarm when full.
- Timer settings are listed as 6, 8 or 12 hours, with sleep mode and seven independently controlled gradient lights.
- The screen is claimed to turn off after 10 seconds of inactivity. The listing also claims 30 decibels in sleep mode.
Reference price: £89.99
Price checked: 13 Nov 2026
View offerAhead of Black FridayExplore the selectionPros and cons
Pros
- A transparent tank and claimed full-tank shut-off with an LED alarm make it easier to monitor collection and know when the tank needs attention.
- Timer choices and a screen-off feature offer practical control for bedroom use, where display light can be distracting.
Technical specifications
12 specifications| Brand | CosmartAir |
|---|---|
| Model | BW406 |
| Colour | Black |
| Tank volume | 3000 Millilitres |
|---|---|
| Claimed collection rate | up to 750 ml/day (at 86°F and 80% RH) |
| Claimed floor area | 640 Square Feet |
| Power consumption | 40 watts |
|---|---|
| Claimed 24-hour energy use | 0.96kWh |
| Timer settings | 6, 8, or 12 hours |
| Sleep-mode noise claim | 30 decibels |
| Dimensions listed | 33D x 15W x 25H centimetres |
|---|---|
| Material listed | Acrylonitrile Butadiene Styrene (ABS) |
What to know before buying
Listing details to confirm
The listed 3,000 ml is the tank volume, while the separate collection claim is up to 750 ml/day at 86°F and 80% RH. The 640 Square Feet coverage claim is also not accompanied by operating conditions, so do not treat it as guaranteed room performance. The listing's 40-watt draw and 0.96kWh for 24-hour operation are arithmetically consistent, but real energy use and moisture removal will depend on conditions.
What’s in the box
Included- Power cord
- User manual
Who is it for?
A good fit for
- Buyers looking for a small-room dehumidifier with a transparent tank, timer and sleep-mode controls.
- People who want adjustable colour lighting and a screen claimed to switch off after inactivity.
Less suited to
- Buyers who need independently verified performance for a large or persistently damp space.
- Anyone seeking a dehumidifier with a confirmed collection rate across a range of room conditions.
Customer reviews on Amazon
- 5 stars
96% 96% - 4 stars
0% 0% - 3 stars
4% 4% - 2 stars
0% 0% - 1 star
0% 0%
The supplied evidence contains aggregate ratings but no written customer feedback. The rating distribution is strongly positive, with a small three-star share, but it cannot show what customers liked or disliked. For buyers considering bedroom use, the listed sleep-mode and timer features are relevant claims, not proof of customer experience or measured performance.
Frequently asked questions
What is the tank capacity?
The listing gives a tank volume of 3000 Millilitres. It separately claims collection of up to 750 ml/day at 86°F and 80% RH.
What timer settings are listed?
The listed timer options are 6, 8 or 12 hours, and the feature description says the timer can also be disabled.
Does it switch off when the tank is full?
The listing claims automatic shut-off and an LED alarm when the tank is full.
What is claimed about sleep mode?
The feature description claims operation as quietly as 30 decibels in sleep mode and says the screen turns off after 10 seconds of inactivity.
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