Best humidifier for hard water

Which humidifiers for hard water are best?

Hard water is called “hard” because of the abundance of minerals that it contains. Due to the processes that humidifiers use to vaporize water, all of those minerals can potentially wind up in the form of mineral dust, which quickly gathers on the surfaces of your room, or worse, it can be inhaled and cause respiratory problems. There are some options to mitigate these problems if you’re stuck with hard water.

That said, a good humidifier for hard water to use is the HoMedics TotalComfort Warm and Cool Mist Ultrasonic Humidifier.

What to know before you buy a humidifier for hard water

Evaporation types

Humidifiers use one of four evaporation types: steam, evaporation, ultrasonic and impelling.

• Steam: Steam humidifiers heat water to boiling and expel the steam into the air. They’re one of the most hazardous types of humidifiers thanks to their heating elements and they can add large amounts of heat to your home, but this technique does help to keep minerals out of the vapor.
• Evaporation: Evaporation humidifiers use wicks and fans to send water vapor into the air. This technique is the most restrictive on minerals but can be harder to track down.
• Ultrasonic: Ultrasonic humidifiers use sound waves to create a mist that’s then dispersed, but this also allows the most minerals to escape into the air. Warm mist action can mitigate this somewhat, but try to find an ultrasonic humidifier that uses a filter to catch the minerals.
• Impelling: Impelling humidifiers are essentially archaic versions of ultrasonic humidifiers; if you find one you should keep looking.

Cool mist vs. warm mist

Most modern humidifiers have cool and warm mist settings, each with hard water caveats.

• Cool mist: Cool mist humidifiers allow the highest amount of minerals into the air. If you want to use a cool mist setting, ensure you either have a filter to catch minerals before they escape, or use it sparingly.
• Warm mist: Warm mist humidifiers allow fewer minerals into the air as the minerals get left behind during the heating process. The downside is that all those minerals get left behind in the tank, requiring a higher frequency of cleaning than any other humidifier.

What to look for in a quality humidifier for hard water

Capacity

The capacity of your humidifier determines how often you need to refill it as well as how long it can run continuously. Humidifiers have a large range of tank capacities, anywhere from half a gallon to nearly 2 gallons.

Demineralization filters

Most humidifiers today are filterless, as many consumers find the necessity of changing one aggravating. However, a demineralization filter-compatible humidifier can eliminate most, if not all, of the downsides to using hard water. This will require recurring cost, however, making the recurring purchase of purified water for a filterless humidifier just as suitable a solution.

How much you can expect to spend on a humidifier for hard water

Humidifiers in general can be as inexpensive as $20 or run as high as $150 or more. Most humidifiers cost somewhere in the $50-$100 range though a humidifier with functions necessary to handle hard water will likely be on the higher end of the cost spectrum.

Humidifier for hard water FAQ

What’s the best humidity percentage to keep my room at?

A. Most consider 45% humidity to be the perfect setting for their homes but many people have different preferences. Some prefer to keep humidity as low as possible while others, especially plant lovers, keep their humidity as high as 70%. If you’ve never used a humidifier before, then start at 45% and adjust until your home feels just right.

What sort of uses is a humidifier good for?

A. Humidifiers are mostly used to combat the effects of dry air, which can lead to many maladies like sore throats and nose bleeds. They can also be used to alleviate the symptoms of colds and allergies and even be used to better maintain certain kinds of houseplants.

What’s the best humidifier for hard water to buy?

Top humidifier for hard water

HoMedics TotalComfort Warm and Cool Mist Ultrasonic Humidifier 

What you need to know: This HoMedics humidifier is perfect for use with hard water, thanks to its included demineralization filters that allow you to fill and forget.

What you’ll love: This humidifier has a massive 1.7-gallon tank capacity split between two easy-fill tanks, which allow the humidifier to run for up to 80 hours without needing a refill. Antimicrobial technology helps prevent the buildup of mold and mildew.

What you should consider: You’ll need to replace the filters more often with harder water, which can quickly add up. There’s no smart home integration as with similarly priced humidifiers.

Where to buy: Sold by Amazon

Top humidifier for hard water for the money

Honeywell Cool Moisture Humidifier

What you need to know: This budget humidifier for hard water is an excellent choice for those who don’t regularly require the use of a humidifier.

What you’ll love: As this is a cool-moisture option, it’s easy to clean. It includes a filter to capture minerals in hard water that might leave behind a white residue. Made for small- to medium-sized rooms, its runtime is 18 hours. 

What you should consider: Some reported that it’s not as quiet as the company claims it to be. 

Where to buy: Sold by Amazon

Worth checking out

LEVOIT Warm and Cool Mist Humidifier

What you need to know: This multifunction and smart-home-capable humidifier is a good choice for hard water, though its cool-mist setting shouldn’t be used.

What you’ll love: The warm mist function offers up to four times faster vaporization than other warm mist humidifiers. A 6-liter tank capacity offers up to 50 hours of usage. Sensors automatically detect and adjust the humidity of the room. A remote control is included. 

What you should consider: The ultrasonic vaporization method means that the cool mist function will easily mix minerals with the water vapor, preventing safe usage.

Where to buy: Sold by Amazon

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Jordan Woika writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.