Why Does Air Purifier Have White Dust?

In order to successfully fight white dust, you should first figure out where this powder is coming from.

Water-based air purifiers can produce white dust if you fill them with hard water. In most cases, however, it’s not your purifier that’s producing the powder – its filters are simply not able to filter out the white dust that is coming from your humidifier or the HVAC system.

Why Do I Have White Dust in My House?

Usually, the biggest source of white dust is ultrasonic humidifiers. But the truth is that this powder can be created by plenty of other things as well:

  • The dust from the carpet that is released during foot traffic can look like white powder
  • The dust might be coming from open doors and windows
  • The heating and cooling system is a large source of white dust – the gaps in the ductwork might be drawing in a lot of dust from the basement
  • Even paper products can contribute to the formation of the powder – toilet paper and tissues can release ‘fuzzies’ when you use them
  • The white dust can also be a result of a chemical reaction between the furnace exhaust, zinc, and galvanized steel

Read: Which Is Better An Air Purifier Or An Air Scrubber?

What Is the White Powder Coming Out of Vents?

  • If you have a new HVAC system, then the white dust might be the remnants of oil or film
  • In HVAC systems that have a humidifier, the white powder can be caused by this specific component, if you live in an area where hard water is an issue
  • If you’re living somewhere near the coast, then the high salt content in the air might be to blame
  • Do bear in mind that chalky white powder coming out of the vents can also be an indication of a carbon monoxide leak

What Does White Dust Look Like?

You are dealing with white dust if you have noticed white specks on different surfaces around your house that are located close to the humidifier or the heating and cooling system.

Read: Does HVAC Purify Air?

Why Does My Air Purifier Have White Dust?

There are two things that you should be aware of when it comes to white dust and air purifiers.

  1. There are water-based air purifiers that use water as a filter. The majority of them also act as humidifiers, so if you’re filling the device with tap water, then the minerals might end up settling on the furniture in the form of white dust.
  2. There might be another device in your house that is producing white dust (like an ultrasonic humidifier) and not all air purifiers would be able to filter out that dust. Electrostatic filters, for example, have a MERV rating between 1 and 4 which means that they are able to capture less than 20% of the dust.

White Dust on Air Purifier

White powder might accumulate on your air purifier if it is already present in the house. Portable humidifiers and those installed in the actual HVAC system can create white dust and ‘push’ it out into the rooms.

Read: Why Is Air Conditioning So Expensive?

Why Is My Dust White?

White dust is created when water with high mineral content (hard water) is used in humidifiers and some air purifiers. 

The things that make the powder white are, most likely, calcium and magnesium. Both of these elements are silvery-white.

How Do You Get Rid of White Dust in the Air?

To get rid of the white powder for good, you would have to tackle the root cause of the problem.

  • Start using soft water in your air purifier, humidifier, and heating and cooling system. In the majority of cases, tap water has high mineral content, so you would have to go for distilled, purified, or demineralized water instead.
  • The device that you’re using might have a special slot for a demineralization cartridge – these things are able to trap the minerals before they get released into the air.
  • If you have a water-based or electrostatic air purifier or an ultrasonic humidifier, then you might want to consider switching to another device. Activated carbon air purifiers, HEPA air purifiers, and ionizers are not capable of creating white dust.

Why Is My Humidifier Leaving White Dust?

If both of the following statements about your humidifier are true, then it is, most likely, producing white dust:

  1. You have an ultrasonic humidifier
  2. You tend to fill the tank with tap or potable water that has high mineral content

Is the White Dust from Humidifiers Harmful?

According to the EPA, there are no adverse health effects associated with white dust and humidifier use. However, a child once got a lung injury after accidentally inhaling the mineral dust produced by a humidifier.

By the way, if your humidifier is dirty, it might be releasing various bacteria and mold spores into the air.

Cleaning the device on a regular basis and using distilled water will help avoid these issues. 

Read: Ductless Vs Central Air System – What Is More Efficient?

Which Humidifier Does Not Produce White Dust?

Steam vaporizers and evaporative cool moisture humidifiers are the types that do not produce white dust. 

That is because the water evaporates inside the device. The vapor is then released into the air and all the impurities that were present in the water get left behind.

Are Air Purifiers Good for Dust?

HEPA air purifiers have a High-Efficiency Particulate Air filter. Those can filter out up to 99.97% of all airborne particles (but only the ones that are larger than 0.3 microns).

The devices with carbon-based and electrostatic filters are not very good at dealing with dander and dust, but they’ll help you with odors.

Where Is the Best Place to Put an Air Purifier?

You should place the air purifier somewhere in your breathing zone. On a nightstand in a bedroom or on a small table in the living room, for example.

Ideally, you would want to have the device in an open area. The purifier is going to work best when having at least one foot of space all around it (this means that you should avoid tight spaces and corners).

Read: How Do I Know If My Air Ducts Need To Be Cleaned?

How Do I Know If My Air Purifier Is Working?

  • Check the airflow – if the unit is not blowing any air, then it’s not working properly.
  • Inspect the internal filters – a dirty filter means that the device is doing a great job at purifying the air (don’t forget to replace the filter though)
  • Use an air quality monitor – you would have to get a baseline reading when the purifier is off and then compare it to the reading that you’ll get after the purifier has been on for a couple of hours.

How Long Does It Take an Air Purifier to Clean a Room?

The exact time is going to depend on the type of purifier and the size of the room. In general, it should take the device 30-45 minutes to clean the air in a small room and up to 4 hours – in large rooms.

What Happens If You Dont Clean Air Purifier?

  • Some parts of the air purifier (like the motor) will start to fail
  • The devices will become a breeding ground for bacteria
  • Air in your house might become stagnant and the air quality will get worse
  • The cost of running the purifier will increase as the device would have to overwork

Can Air Purifiers Make You Sick?

Ionizers and the air purifiers that generate ozone might be dangerous for your health. Ozone, for example, can cause long-term damage to the lungs.

Air purifiers that use filters are the safest devices. However, the effectiveness of a lot of those is questionable as some floor models are able to move less than 100 cubic feet of air per minute through their filters.

Dirty air purifiers also pose a health risk as they can become a breeding ground for various germs. 

Do Air Purifiers Work with Covid?

By itself, a portable air purifier is not enough to protect you from COVID. With that being said, some types of these devices can help reduce airborne contaminants (including viruses), if utilized correctly.