It’s no secret that when you buy an air purifier, you are unwittingly signing up for the filter of the month club.
Air purifiers, almost more than any other appliance, require upkeep.And when you’re talking about the upkeep as being replacing filters,
It can get very expensive.
But there is a style of air purifier that does not require any costly filter replacements and uses one of the most available resources you can find to work.
Water.
That’s right. Instead of the HEPA and carbon filter combo that most air purifiers require, this type of air purifier uses regular tap water as a filter.
Can You purify air with water?
“Water Air Purifiers” come in 2 different types:
- Small tank Revitalizers
- Air Washers
A Revitalizer is a small multi-purpose appliance that combines an air purifier,
A humidifier, and an aroma diffuser.
An Air Washer is a water air purifier that covers a much larger room than a Revitalizer and reduces a higher amount of airborne pollutants.

Revitalizer
This unique air purifier draws air in and through a tank of water that is being swished around, and then blows the air out the other side after it has been washed by the water.
The effect is something like how the air feels after a nice heavy rain.
The unit also works as a humidifier because of the moist air that is being blown out of the water chamber.
These water based air cleaners also come with a bottler or two of essential oil to drop into the water turning the unit into a aromatherapy diffuser as well as a purifier.



These types of water air cleaners are a great idea as long as you understand that they are a jack-of-all-trades type of unit that will marginally work as a air purifier, humidifier, and diffuser but are not designed to do any of these things especially the best.
But they are inexpensive and usually run below the $50 to $75 range.
And the person who buys this is probably not looking for the best in any of these categories.
The durability is solid and there’s not too many parts besides the small motor that could go out. so the chances of buying a lemon are pretty slim.
Since they are a humidifier, they do require cleaning to ensure that mold and mildew do not build up in the machine.
But that only takes snapping a couple of parts off and putting them in the dishwasher or washing them off by hand.
One thing is, some of the advertising claims say that because these create a rain effect, they also manufacture negative ions.




Negative ions are not produced as much by rainfall in a storm but by lightning.
So unless you buy a model that has an additional negative ionizer, you’re not going to get negative ion production with these machines.
Air washer
An air washer is also a hybrid appliance that combines an air purifier and a humidifier and like the revitalizers, many of them also give you the option of adding a drop of scented oil as a means of adding a fragrance or masking an odor.
The difference is that:
Air washers are designed to cover a larger square footage and are equipped to handle a much heavier level of bad indoor air quality.
These are a 2 in 1 Humidifier and water-based air purifiers that take as much as 1.5 to 3 gallons of water to fill.




How do Air Washers Work?
Air is drawn into the machine and goes through a 2- 4-Part filtering process called disc stacks that essentially scrub the air with water and deposit the air pollutants into a separate basin. The air is then blown, out of the other side of the machine “cleaned”.
The amount of air that is being washed and moved through the machine also makes it much more efficient at adding humidity into the air in the form of a humidifier.
But unlike the revitalizer that acts as a humidifier only in that it creates moisture in the air cleaning process,
Air washers can control the amount of humidity being created and come with hygrometer and hydrostat gauges to measure and set the humidity to your liking.
The price difference for these is substantially higher. Ranging from $250 to $450.
Air washers also require regular cleaning because of the chance of mold and mildew growing in the machine. But it is a very easy process that can be performed in a very short time.
Water air purifiers are good at removing larger particulate air pollution.
Namely pollen and dust, and pet dander
But although they are not as efficient at removing other types of pollutants like mold spores as a HEPA air purifier would be, they do help reduce these type of pollutants also.
As for odors, the fact that many of these come supplied with extra essential oils to add fragrance in the air tells you how good they are at actually removing odors.



Adding Aromatherapy with Essential Oils
But that is part of the charm and there is a big audience of people who like to treat their air with essential oils.
As a humidifier, an air washer is the absolute best type of humidifier you can buy.
But as an air purifier, there are definitely better, more efficient ways to clean air.
Air washers do well at removing particulates from the air as small as 1.5 microns. HEPA filters on the other hand are manufactured to capture particular to smallest .03 microns. And almost all HEPA air purifiers are coupled with carbon air filters that are capable of removing even much smaller airborne offenses. Carbon filters are also well known for their capacity of absorbing odors, something an air washer does not do well.
Another aspect of using water air filtration that doesn’t quite add up is that there are many times throughout the year, especially this summer months where adding more humidity to the air would be unbearable.
In fact the opposite is true, placing a dehumidifier in the house at that point would actually be better for the air quality and would reduce dust mites which thrive in humidity. Dehumidifiers also take the strain off of overworked HVAC units and air conditioners when the humidity is high.
There is also the point that putting essential oil into the humidifier it’s not something a lot of people suggest because humidifiers come with nebulizers that are meant to create a fine mist of moisture. Oil can leave residues that clog up the tubes that are required for them to work.
At this point, you’ve got to be wondering if buying a 2 in 1 humidifier and air purifier is worth it.
Pros and cons of water air purifiers.
Pros
- No filter replacements ever
- The best humidifier money can buy
- Can provide air cleaning, humidity, and aromatherapy all in one
Cons
- There are better machines for cleaning air
- Not all climates need extra humidity
- Humidifiers can become moldy if not regularly maintenanced.
- Adding essential oils to water does not make the best aromatherapy diffuser and can leave residue that eventually will clog a nebulizer.
Common Questions
Can you put any essential oil in the water air purifier
or does it take a special kind, just for the air purifier?
It would be better to stay with the manufacturers oil since they are formulated to work better in water.
But putting essential oils in humidifiers is not a new thing and some humidifiers even come with a place to put the oil.
Just make sure you don’t put it in a nebulizer type humidifier.
What’s the difference between an air purifier and humidifier?
An air purifier is a machine that cleans the air and a humidifier is a machine that adds humidity or moisture into the air.
A water air purifier or air washer uses water to clean the air as well as add moisture to the air.
What is the difference between a humidifier and a diffuser?
A humidifier adds moisture to the air and a diffuser is a device to spread aromatherapy scents or essential oil scents into the air.
What is the difference between a revitalizer and an air washer?
The main difference is the size and volume of air that can be cleaned.
Also though some air washers do come with a bottle of essential oils to add to the water, air washers are typically just two in one air purifier and humidifier combos,
whereas a revitalizer is actually sold as a three-in-one unit that combines an air purifier, a humidifier and a diffuser.