The Best Humidifiers for Hard Water

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Humidifiers have many benefits from keeping your skin from drying out to helping with respiratory problems. Unfortunately, humidifiers and hard water mix like oil and water. The minerals in hard water are often dispersed into your room and can cause respiratory problems (ironically) and leave white dust everywhere. These minerals will also clog up your humidifier too. Purchasing distilled bottled water does solve this problem but can get very expensive. In this guide I have four solution to this problem, each with their own pros and cons.

The best humidifier for hard water is one which has a built in filter. This filter will remove the minerals before they are emitted from the humidifier giving you a cleaner mist, free from white dust. Another option is to buy a warm mist humidifier. These don’t emit white dust but will require regular cleaning. A third option is to buy a distiller to create your own distilled water for your humidifier. The final option is to use demineralization cartridges in your humidifier.

Why Is Hard Water Problematic for Humidifiers?

Hard water contains higher levels of minerals like calcium and magnesium than soft water. These minerals aren’t harmful when you drink them and might actually be beneficial to your health. However, hard water can be problematic for pipes and appliances (like humidifiers).

There are two main types of humidifier and hard water affects them in different ways.

  • Cold mist humidifiers – the problem with using hard water in a cold mist humidifier is that the minerals are dispersed into the air with the water. This isn’t good for your lungs and can be particularly problematic for people with asthma. To make matters worse, these minerals eventually settle forming what is known as “white dust”. This dust doesn’t exactly look good when it’s covering your room and can cause problems if it gets inside electronics.
  • Warm mist humidifiers – warm mist humidifiers work differently and heat the water until steam is emitted. This means the mist is purer than with cold mist humidifiers, however, since the minerals are not being dispersed with the water, they will build up inside the humidifier causing damage. This is a problem with cool mist humidifiers too, but it isn’t quite as bad because a lot of the minerals are dispersed with the mist.

4 Solutions to Consider

Now I will go over four solutions that solve the problem of hard water with humidifiers. Whether you want a cool mist or warm mist humidifier, at least one of these solution should work for you.

1. Cool Mist Humidifier With a Filter

As I previously mentioned, cool mist humidifiers emit minerals from the hard water into your room which isn’t good. However, some units come equipped with a built in filter designed to tackle this problem by filtering out these minerals. Unfortunately, the filers in these units get clogged up quite quickly and they will need replacing regularly, especially when you are using hard water. They aren’t cheap either so the costs will start to add up quickly. This method does work, but it also gets expensive.

The benefit of a cool mist humidifier over a warm mist humidifier is that they are safer to use around kids. It is not recommended to use a warm mist humidifier around kids because of the heating element. Cool mist humidifiers will also help to cool your room down which is great for the summer or if you live in a warmer climate. However, a downside to cool mist humidifiers is that they are usually loud than warm mist models.

If you would like a cool mist humidifier but don’t want the expensive of replacing the filters, check out solutions 3 and 4 in this guide. However, if you are interested in a cool mist humidifier with a built-in filter, check out the Honeywell HCM350W. It has a 1 gallon tank and is ideal for bedrooms and any medium sized room.

Honeywell Cool Moisture Humidifier, Medium Room, 1 Gallon Tank, White – Invisible...
  • CLEANER INVISIBLE MOISTURE – Honeywell Cool Moisture Humidifier...
  • EVERYDAY COMFORT – This humidifier for home features evaporative...
  • EASY TO USE – Featuring a large 1.1 gallon, easy-fill, self-standing...
  • HUMIDIFIER FOR BEDROOM – As the ideal humidifier for baby, this device...

2. Warm Mist Humidifier (With Frequent Cleaning)

A warm mist humidifier won’t emit minerals into the room like a cool mist humidifier, however, minerals will build up inside the tank and clog it up. If you are willing to keep on top of cleaning it, a warm mist humidifier is a good choice for hard water. The main benefit of this solution is that it is cheaper, with the trade-off being that it will involve more maintenance.

A warm mist humidifier will add some heat to your room so it is a good choice for using in the winter or cooler climates. Warm mist humidifiers are usually quieter than cool mist humidifiers so are great if you are sensitive to noise. However, due to the heating element and the risk of burns, it is not recommended to use a warm mist humidifier around children.

If you’re considering this solution, check out the Vicks 1-Gallon warm mist humidifier. It has a 1 gallon tanks and is perfect for medium sized rooms. It’s also super quiet, has 2 output settings, and a medicine cup to use with liquid inhalants.

Vicks Warm Mist Humidifier, Small to Medium Rooms, 1 Gallon Tank...
  • WARM MIST HUMIDIFIER – Vicks Warm Mist Humidifier helps to ensure...
  • COUGH AND CONGESTION RELIEF – Vaporizers for bedroom and home can be...
  • QUICK AND EASY TO USE – This filter-free humidifier can be used with...
  • HUMIDIFIERS FOR BEDROOM AND MORE – A warm mist humidifier is great...

3. Water Distiller

If you want to invest a little bit more upfront, you can buy a water distiller to remove the minerals from your hard water for use in any humidifier. A distiller will set you back quite a bit at the beginning, but you can usually pick one up for under $100. You might find it comes in useful elsewhere too if any of your other appliances have trouble with hard water.

The benefits of this method is that there won’t be ongoing costs for replacement filters and you won’t need to clean your humidifier quite as often (although it is still a good idea to give it an occasional clean).

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4. Demineralization Cartridges

Another option to consider is to use demineralization cartridges in a cool mist humidifier. (It is not a good idea to use these in a warm mist humidifier because of the heating element.) This method is similar to the first method except the filter isn’t built-in. You do have the same problem in that you will need to change the cartridges and the costs can add up, but demineralization cartridges are usually cheaper than replacement filters.

If you like the idea of this solution, check out the demineralization cartridges below and the
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Hard water is certainly problematic for humidifiers, however, there are solutions to this problem! A cool mist humidifier with a built in filter will help to keep minerals from hard water out of the air and reduce white dust but you will need to regularly replace the filters. A warm mist humidifier is a great choice if you are willing to clean it regularly. Or you can use a distiller or demineralization cartridges with any humidifier. Each option has it’s pros and cons, but hopefully you can find the best solution for your situation.

Last update on 2023-02-07 / Affiliate links / Images from Amazon Product Advertising API

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