A comparison of air washers: how air purification with water works

Keeping the air quality high is always a good idea. The air washer is an aid to indoor air purification. It purifies the air with the help of water and does not require an additional filter.

By the way: Air washers are now a rarity on the market - most manufacturers now rely purely on air purifiers with HEPA filters. Venta is an exception here and is still the leader in the air washer sector. Many years of experience and sophisticated technology make Venta a true specialist in this segment. That's why three Venta models are included in the comparison.

In this article, I'll give you the most important facts about air washers and how they work. I will then present a ranking of air washers that I think are worth recommending.

If you want to jump straight to the ranking, click on one of the links in the following ranking summary:

Recommended air washers

Venta LW25 Comfort Plus
Beurer LW230
Venta AW 730
Venta LW15

But now let's take a look at how such an air washer works and how it is constructed!

Functionality & structure of the air washer

The design of an air washer is not particularly complicated. Its mode of operation can also be summarised quickly:

The air is sucked in with a rotor
Rotating louvres wetted with water filter small particles (e.g. dust) from the air
The now cleaner air is blown out again

The first and last steps are relatively self-explanatory. The appliance contains a rotor that sets the air in motion. It is sucked in at one side of the appliance, then guided through the interior and blown out again at another side.

FAQ: How does an air washer work?

An air washer cleans the air using water. The sucked-in air is passed through rotating humidification discs or drums that rotate in a water bath. Dust, pollen and other particles stick to the wet surface and are trapped in the water. At the same time, the air is humidified - without any filters or chemical additives. Ideal for allergy sufferers and during the heating season!

The true Magic takes place inside. This is where the water tank is located. It is filled to such an extent that the rotating cylinder inside the appliance is partially submerged in water.

The cylinder in turn consists of many small louvres or is at least shaped in such a way that it has the largest possible surface area and air can flow around or through it.

When the air washer is switched on, the rotor blows air into and around the cylinder, which begins to rotate. The air that is immersed in the water as a result of the rotation Lamellae are constantly wetted with a thin layer of water. In this way, the air and the particles in it quickly come into contact with the water.

Dirt particles, dust or other particles adhere to the water - the air is literally washed. The air is also humidified during this process:

A strong air flow and a large surface area of water favour evaporation.

In a nutshell: The air washer utilises wind and water with a large surface area to bind particles from the air.

Concrete benefits of an air washer

Now you know how an air washer works. But when and where exactly does it make sense to use an air washer? Let's find out now!

What an air washer can do

The air washer can be used to filter small particles (dust, pollen, bad odours, animal hairs, etc.) from the room air. These particles are bound to the water in the tank.

An air washer can wash 50m³ or more of air per hour, depending heavily on the model. The air in a room with 20m² and a ceiling height of around 3m could therefore be scrubbed in just over an hour in good conditions.

Compared to other devices, the air washer has a Improving the indoor climate a rather low electrical consumption. Most appliances get by with far less than 20W. You can find out how much it will cost you to operate with this handy calculator:

You can adjust the values in the calculator so that they correspond to your expected usage behaviour.

Where to use an air washer

In principle, it is always and everywhere a sensible idea to endeavour to create a good indoor climate and clean air. But in some rooms it is particularly useful.

Kitchen

As the air washer is able to bind odours, among other things, it can be used accordingly. For example, it can be used in the kitchen after cooking to quickly neutralise odours.

This is particularly appropriate in shared kitchens in order to be considerate of the noses of other residents and users. Garlic, onions or strong spices are good examples of odours that should ideally not linger in the kitchen air all day long.

Households with pets

As cute as our furry friends are, every now and then they are the cause of bad odours - for example, if their fur has become wet in the rain. In this case, an air washer is helpful to get the odours out of the air.

Smoking households

The rapid binding of smoke particles protects the equipment and restores it to its normal state more quickly after smoking.

Rooms with lots of textiles

Textiles such as carpets, curtains, sofas, etc. lose small fibres which, in combination with house dust, turn into annoying little fluffs. The air washer can also help against this.

Households with many members

Unfortunately, we humans are the main cause of house dust. We lose about 10g of dander per day^[ 1 ]. The more people living in a household, the more dander. For this reason, more frequent vacuuming is necessary in households with many residents. The air washer can also be used at this point to filter this dander out of the air.

Recommended air washers

Here is my ranking list of air washers that I think are worth recommending. I have endeavoured to compile them according to the most objective criteria possible and have selected a suitable product for each price category.

If you have any questions about the list or think that an air washer is missing or has been wrongly included in the ranking, please send me an e-mail to: maxmarx1991@gmail.com

Venta LW25 Comfort Plus - Quiet, smart & effective

Suitable for continuous operation
Low maintenance and easy to clean
Fragrance function and various modes such as sleep mode
Ideal for allergy sufferers

Takes time in very dry air
Design could be better

The Venta LW25 Comfort Plus humidifier is the absolute test winner for me. The automatic mode does the work for you by automatically regulating the humidity - a great advantage, especially in the cold season, when the air is often very dry. At the same time, it filters dust and other particles out of the air and ensures an all-round pleasant indoor climate.

With only 24 dB(A) it works as quietly as a whispereven in the bedroom. I was particularly impressed by the extremely low energy consumption of just 3 watts in continuous operation, which makes it extremely efficient. The cold evaporation without filter makes maintenance much easier, and the Large 7-litre tank provides for Long running timeswithout having to constantly top up with water. In Rooms up to 45 m² the Venta distributes the humidified air evenly and significantly improves the air quality.

I was particularly impressed:

extremely quiet operation, ideal for bedrooms or offices,
low power consumption, perfect for continuous operation,
easy maintenance thanks to cold evaporation without filters, and
effective filtering of dust particles, which is particularly beneficial for allergy sufferers.

The appliance also offers a fragrance function that can be used discreetly. One small point: At very low humidity levels, it takes a while to reach the desired humidity, but this is normal for appliances of this size.

Who wants something for smaller rooms should take a look at the Model LW15 for approx. 140 € or for larger ones the LW45which offers similar functions. For me, however, the LW25 Comfort Plus remains the clear favourite - the test winner for clean, pleasantly humidified air in larger rooms!

Venta LW 25 - Provides clean air

Highly efficient air humidification thanks to VentWave 3D technology
Ingeniously simple ease of use with fully automatic control
High-quality sensor technology for real-time humidity display and control
Natural reduction of pollen and house dust - important for allergy sufferers
No filter mats - water is the filter: hygienic, easy to clean, uncomplicated

FAQs for the Venta LW45 Comfort Plus

It depends on the size of the room. With open doors, a certain amount of air exchange can take place, but for optimum results, one appliance per room is recommended.

It depends on the room layout. For a 70 square metre flat with several rooms, it might be more efficient to use several appliances.

No, the Venta is a humidifier and does not clean aerosols or viruses.

Yes, some essential oils or fragrances are compatible, as long as they are suitable for the Venta.

Yes, the automatic programme adjusts the appliance's performance to the humidity and saves energy.

A minimum distance of 50 cm should be maintained in all directions to ensure optimum air circulation.

Beurer LW 230 Air washer - effective & inexpensive

Noticeable improvement in air quality
Ideal for allergy sufferers
Very quiet in night mode
Good effect on dry heating air

Partially audible at higher levels
Fuel gauge can be inaccurate

Whoever is under dry air, cough or irritated mucous membranes suffers from the Beurer LW 230 Air washer take a closer look. The appliance does not clean the air with conventional filters, but in a natural way - by leads through water. This is how Effectively binds house dust, pollen and animal hairand at the same time the air is pleasantly humidified. This is a noticeable relief, especially for allergy sufferers or for use in the bedroom.

In the test, the air washer impressed with a Quiet operationa large water tank (little refilling!) and a discreet designthat blends in well with the living room. It really comes into its own in the bedroom: Approx. 1-2 hours on a high setting before going to bedthen the Whisper-quiet level 1 - the device can run all nightwithout disturbing. The only small disadvantage: the Light indicator is not dimmablebut can easily be covered with a T-shirt or adhesive tape.

The effect is clearly noticeable: Less coughing at night, less dry or runny nose, no burning eyes. The skin also feels less dry in the morning - a pleasant side effect that is quickly appreciated. Anyone who has ever experienced how Purified and humidified air in the room, you don't want to go back.

Although the LW 230 is more of a Humidifier with cleaning function than a pure air purifier, but it fulfils exactly what many are looking for: Natural fresh air without filter changes or chemicals. From our point of view a Sensible and sustainable investment - especially for everyday use during the heating season. An appliance that you no longer want to do without.

Beurer LW 230 Air washer

Combination device for air humidification and air purification: The sucked-in air absorbs water molecules at the humidifier discs, at the same time house dust, pollen, animal hair and odours are washed away
Particularly hygienic: disc pack and water tray can be put in the dishwasher
Whisper-quiet operation: The LW 230 is quiet in all three power levels and is suitable for use at night. When there is no more water, it switches off automatically
Room humidifier for dry air with the dimensions (LxWxH): 30 x 30 x 34 cm works extremely energy-efficiently with max. 7 watts and can also be controlled via an external timer
Simple operation: Self-regulating humidification through cold evaporation suitable for rooms up to approx. 40 m², with fill level indicator and blue LCD display

FAQs about the Dreo Nomad One

In my 22 m² bedroom you can clearly feel the humid air - the effect is noticeable, even on the skin and mucous membranes.

Yes, I had significantly less coughing at night, my nose was no longer dry or runny and my eyes were hardly irritated at all.

Level 1 is practically inaudible. Level 3 is audible, so it is only used before going to bed.

Yes, I run it on level 1 every night - doesn't disturb my sleep.

Unfortunately, you can't switch it off. I put a dark-coloured T-shirt over it, then it fits.

It filters out dust and hair well, but does not replace a HEPA filter - it is more of a humidifier with a cleaning function.

Depends on the level. For me, one filling is enough for one night plus operation before going to bed.

Yes, a clear recommendation for bedrooms and sensitive mucous membranes - I wouldn't want to be without it.

Venta AW 730 - High price with top results

For optimum 40-60 % humidity
5 power levels
Quiet at level 1 e.g. 22 dB
Room size up to 50 m²
Perfect for allergy sufferers
High-quality workmanship & elegant design

Relatively large and heavy
App with minor weaknesses (e.g. timer missing)

The Venta AW 730 is a high quality 2-in-1 air purifier and humidifierwhich is particularly suitable for medium-sized rooms up to 50 m² suitable. Even when unpacking, the High-quality workmanship and the modern design that blends harmoniously into living rooms or offices.

In use, the device impresses with its Noticeable air improvementThe Humidity rises reliably and remains stable in the optimum range between 40-60 %. At the same time, the device filters Fine dust, pollen, viruses and even formaldehyde with an efficiency of 99.97 % - Ideal for Allergy sufferers and sensitive persons.

In the Venta is very quiet in operation. Even on Level 3 it remains pleasantly calm. In the Sleep mode it is almost not audibleThis makes it ideal for night-time use in the bedroom. Noise such as rattling did not occur in our test, but were occasionally reported by users.

The Operation either directly via the Touch display, per App or via Voice control (Alexa/Google). This makes the control Very comfortableeven if, according to some user reviews, the app is still Optimisation potential (e.g. timer function).

A small disadvantage: Accessories such as hygiene products or filters must be purchased separately. The High weight can be annoying in small flats or if you move frequently.

Conclusion: The Venta AW 730 is a Powerful premium appliancethat the Air humidification and purification combined at a high level. Especially for Dry heating air or allergies the effect quickly and clearly noticeable. The Quiet operationthe Smart range of functions and the Processing quality justify the price - and make the AW 730 a Clear recommendation for a healthy indoor climate.

Venta AW 730 - Ideal for allergy sufferers

2-in-1 air purifier & humidifier: Combined high purification and humidification performance
Removes 99.97% of e.g. fine dust, viruses or allergens up to a size of 0.3μm and formaldehyde gases from your indoor air
Easily achieve the ideal humidity level in your rooms with the hygienic principle of cold evaporation - for optimum 40-60% humidity - WITHOUT HUMIDIFYING MATS AND WITHOUT LONG-LASTING COLD NAPS
Easy to switch the humidification mode on and off - also use it as a pure air purifier
The 5 practical programme levels ensure the right setting for your appliance via touch display, voice control (Alexa & Google) or app - or use our extra programmes: Automatic, Sleep or Turbo mode

FAQs for the Venta AW 730

The AW 730 filters up to 99.97 % of all particles down to 0.3 µm - noticeably cleaner air, especially for allergy sufferers.

It is pleasantly quiet even at level 3. Barely audible in sleep mode - perfect for the bedroom.

In a 50 m² room, the humidity quickly rises to approx. 40 % - the effect is clearly noticeable.

Yes, the device can also be used purely as an air purifier - without any humidification.

Very intuitive: touch display, app or voice control (Alexa & Google) - everything is possible.

High-quality workmanship, modern design - and, according to users, durable and reliable.

Accessories such as sanitiser must be purchased separately. Some users criticise the weight or occasional noise.

Venta LW 15 - Small but mighty

Venta LW 15 - ideal for small rooms

Ingeniously simple, effective humidification technology
Easy operation & cleaning
Natural reduction of pollutants in the air at a room humidity of 40-60 %
Use with tap water
Made in Germany

Quiet (max. 32dB)
Low energy consumption
Low operating costs

More frequent cleaning
Design

In contrast to the other two devices, this air washer from Venta has No additional filters. It only washes the air with water and in the manner described at the beginning of this article described way.

This results in both advantages and disadvantages for operation. On the one hand, you don't have to worry about cleaning and replacing the filters. On the other hand, the air meets the water unfiltered. This means that the dirt and particles that would have remained in the filters now end up in the water. The water in this air washer therefore needs to be changed and the water tank cleaned more frequently.

According to the manufacturer, the tank and cylinders should be cleaned every 14 days. The cleaning agent directly from the manufacturer is ideal for this. It prevents the machine from calcifying and counteracts germs.

The relatively Favourable cleaning agents and hygiene products in combination with a Low energy consumption of 4 watts ensure very low operating costs. The cleaning and hygiene products last a long time, so you rarely have to buy more.

Compared to the other products presented here, this air washer does not have a timer or app control. However, there is nothing wrong with operating it with a timer. This allows you to retrofit the functionality of a timer. The Venta sanitiser comes in a 500 ml bottle and should last a long time. This sanitiser * is especially suitable for this air washer. In addition to the sanitiser, Venta also offers the right cleaning agent * for cleaning the water tank.

FAQs about the Venta LW15 humidifier

It depends on the size of the room. It has helped well with hay fever, but the exact time is difficult to say.

It depends on factors such as room size, ventilation and open doors. For optimum results, the room height and air exchange should be taken into account.

Yes, a larger appliance would make sense, as the humidification performance of smaller appliances is often insufficient.

Yes, it should be about 20-30 cm away from walls and objects so that the moist air can be well distributed.

The room may be too large or there may be too much air exchange so that the output is not sufficient.

No, the appliance humidifies the air but does not cool it.

The LW45 is well suited for rooms up to 60 square metres, but even 10 square metres more should not be a problem.

Yes, especially with continuous operation at a low level, but the LW45 would be better suited for higher rooms.

Conclusion

Air washers are a practical way to improve the indoor climate. They use water to filter dirt, dust and other particles out of the air.

For models with additional filters (activated carbon filter, HEPA filter, etc.), the water tank needs to be cleaned less frequently, but the filters need to be cleaned or replaced every six months or so.

Air washers without additional filters do not require filters to be replaced, but the water tank must be cleaned more frequently. On the one hand, they do not filter as effectively as models with additional filters, but on the other hand, they consume considerably less energy.

Pure air filters are an alternative to air washers. You can find out more about them and their advantages and disadvantages in the following linked article:

I very much hope that I have helped you with this article! If you are interested in the topic in general and want to learn how and with what you can improve the indoor climate, then take a look at the section Indoor climate over 🙂