Some home appliances recommend that you use distilled water, while others recommend that you use tap water. Do you think you know which ones fall into the distilled category? You might be surprised!

Intro

Some water-using appliances recommend distilled water for the best performance, lowest maintenance, and to extend the life of the product. Other appliances don’t recommend using distilled water. These are generalities for modern home appliances. Always consult your owner’s manual for your specific product. We can’t include every brand and every model in one article, so always consult your user manual for manufacturer recommendations for your specific appliance. We will cover a wide variety of appliances and general recommendations for water.

About Distilled Water

Distilled water is created by heating water until it steams and then condensing the steam back into a liquid. This process purifies the water of 99.9% of contaminants like organic and inorganic compounds, as well as dissolved minerals like calcium and magnesium. Distilled water is readily available in most supermarkets, but you can make distilled water yourself at home with minimal difficulty. If you want plenty of distilled water available, you can get a countertop distiller, like this Pure Water Mini Classic Water Distiller.

The tap water in our homes, on the other hand, will vary widely in the volume of minerals dissolved in it, also known as water hardness. This is primarily determined by region, where your water is sourced, and treatment provided before it reaches your tap. Most homes in the United States have moderate to very hard water. Hardness does not affect drinking safety but can cause a residue to build up in your appliances over time. 

Room Humidifiers

Distilled water? Yes.

We all know that the quality of our drinking water is important, but the water vapor in the air around us (humidity) also affects our health and comfort. Many people use a humidifier in their homes to maintain a comfortable humidity level, especially in the winter when the air tends to be dry. One example of a humidifier is the Honeywell HUL430W for medium-sized rooms. This is a cool mist humidifier that uses ultrasonic vibrations to create the mist. The owner’s manual does not recommend a specific type of water but does note that hard water can cause white dust to form which is caused by high mineral content. HVAC professionals recommend using distilled water to prevent this dust.

Another example of a home humidifier is the Lasko UH300 for large rooms. This is a warm mist and cool mist humidifier and the owner’s manual explicitly warns to use distilled water only.

CPAP Machines

Distilled water? YES!

If you or a loved one suffer from sleep apnea, you are probably familiar with CPAP machines. Most modern models include a heated humidifier which provides warm moisture to keep your nasal passages comfortable. If you use the CPAP machine without using the humidifier, your airway may become dry. All CPAP manufacturers recommend or require using distilled water in these humidifiers. The primary reason is to prevent mineral build-up in your machine, but the secondary reason is that some tap water or well water sources contain chemical or biological contaminants that could be harmful to your airway. 

Neti Pot

Distilled water? Maybe, but you have other options.

Millions of people who suffer from sinus irritation from allergies or colds swear by the Neti Pot. This is a means of clearing mucus and debris from the nasal passages. NeilMed, which makes the original Neti Pot, recommends using distilled water or sterile water. Alternatively, you may use tap water that has been boiled for 3 to 5 minutes and allowed to cool. The importance of the type of water used has less to do with minerals than with other potential contaminants. You must actually add minerals (in the form of salt and bicarbonate of soda) to the water in your Neti Pot before you rinse your sinus with it. This saline solution is meant to match your body’s normal saline levels so that the rinse is comfortable in your nasal passages. Without the appropriate level of saline, the water can sting and your sinuses will be uncomfortable.

Steam Cleaners

Distilled water? Yes, or demineralized water.

Steam cleaners are wonderful cleaning tools especially if you are trying to reduce or eliminate the use of chemicals in your home. Instead of cleaning solutions, they use pressurized steam to clean a variety of surfaces. The temperature and pressure levels sanitize upholstery, tile, grout, and much more without the use of chemical disinfectants. Two examples of steam cleaners are the McCulloch MC1375 Canister Steam Cleaner and the Bissell 2747A PowerFresh Vac & Steam. For each of them, the manufacturer’s recommendation is to use distilled or demineralized water. 

Demineralized water, like distilled water, has no minerals in it. Unlike distilled water, it may not be free of other contaminants. Also, demineralized water may not be as readily available as distilled water. 

Mattress Coolers

Distilled water? Recommended, but not required.

Quality sleep is important for our health and for those of us who sleep hot, a mattress cooler like the Sleepme Dock Pro Sleep System can be a lifesaver. This appliance works by circulating chilled water through a mattress pad. According to the owner’s manual, they do recommend using distilled water as this will prevent mineral build-up in the water circulating system. However, you may use tap water if necessary.

Essential Oil Diffusers

Distilled water? Maybe.

People like to use essential oils to make their homes smell nice, for aromatherapy, for yoga practice, and to reduce stress. Some essential oil diffusers use water to dilute the essential oil before creating a mist and spraying it into the air. These types of diffusers have the added benefit of humidifying the air. Some types of oils are also antimicrobial, which is especially helpful during cold and flu season. One such essential oil diffuser, the Porseme 3D essential oil diffuser, recommends using distilled or another purified water. However, “purified” water is a vague term that only means the water has been treated to make it potable but is not specific as to the contaminants removed or the method used. SpaRoom Sonoma essential oil diffuser is another similar type of diffuser. The owner’s manual specifically recommends using tap water and not distilled water. Again, there is no reason given for the type of water recommended, but they do recommend weekly cleaning with vinegar to remove mineral deposits. 

Steam Irons

Distilled water? No, but you may need to mix distilled with your tap water.

Steam irons are basic home appliances that use heat, steam, and pressure to remove wrinkles from fabric. Most Americans believe it’s common knowledge that steam irons require distilled water to prevent mineral deposits in the machine. The owner’s manuals for most modern steam irons, like this Black + Decker Allure Professional and this Rowenta Everlast, however, recommend using tap water. They also recommend that if your tap water is especially hard, you should use a 50/50 mix of tap water and distilled water. Some brands have filters that are supposed to remove minerals from your tap water. And most brands recommend using distilled water for regular cleaning of your iron. 

Electronic Cigar Humidifiers

Distilled water? Yes.

Cigar aficionados know the importance of proper humidity levels in the humidor. Passive humidifiers often use a solution or gel crystals that combine distilled water with propylene glycol to maintain humidity. Electronic humidifiers, like the HumidiCup S1, will monitor and actively maintain appropriate humidity levels for you, and they do recommend using only distilled water. While tap water can provide appropriate humidity, it may also introduce impurities that lead to bacterial or fungal growth in your humidor.

Fabric Steamers

Distilled water? Probably the best choice.

Fabric steamers like the Reliable Vivio 500 are efficient at removing wrinkles from clothing and may be used on more delicate fabrics that cannot be pressed with an iron. This steamer recommends using either distilled or tap water. It also recommends regularly emptying the water reservoir to prevent mineral build-up. Another fabric steamer, the Conair Turbo ExtremeSteam Handheld Steamer, recommends using only distilled water to avoid mineral build-up. In general, it sounds like distilled water is the best option for fabric steamers.

Conclusion

There are many appliances, large and small, around our homes that need water to work. Sometimes distilled water is the best option and other times it is not. The best way to decide is to consult the owner’s manual for your specific product. Hopefully, this gives you an idea of how important it might be to have distilled water around your house.