Preparing for a crisis takes the same level of precision as an actor getting ready for the Oscars. While most people assume a few cases of bottled water are enough when disaster strikes, anyone who relies on a CPAP machine knows that basic supplies won’t cut it.
But having distilled water isn’t just about keeping things “clean” or “pure.” It’s a technical requirement for certain medical devices. They’re designed to use distilled water, and mineral-heavy tap water can cause buildup that damages the hardware, potentially at a critical moment. You might have a few bottles of water stashed away for an emergency, but that supply won’t last long. And you may need it sooner than you think.
The problem with standard “emergency” fixes such as boiling or bleach tablets is that they only kill the things that make you sick. If you run your CPAP on boiled tap water for a week, you could do real damage. Distillation is the only process that leaves those impurities behind, giving you a pure vapor that won’t ruin your equipment or your lungs.
You don’t need to be a chemist to secure a supply, and you certainly shouldn’t wait for a “boil water” advisory to start looking. Here’s how you can distill your own water at home.
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What is distilled water?
Unlike simple filtered water, distilled water is pretty much free of all impurities. That means it’s missing beneficial minerals like calcium and magnesium and will taste a little weird, even though it’s safe to drink. Maintaining and storing a good supply of distilled water is a great way to prepare for emergency situations like hurricanes, floods, wildfires or other natural disasters.
Can you buy distilled water?
Most grocery stores sell distilled water but in the past few years, we’ve seen many shortages. If you can’t find distilled water and need it to prepare for an upcoming storm or to ensure you can run your medical devices, there’s an easy way to make it at home.
Why make distilled water at home?
For people suffering from sleep apnea who use CPAP machines or any other sort of humidifier, distilled water is essential. It’s also useful if you don’t want additional minerals in your water. (For example, distilled water won’t corrode automobile engine parts or create lime-scale buildup in aquariums and it’s easier on your home if you use it to make this all-natural cleaner.)
The process of distilling is simple and requires no special equipment.
Tap water is the easy one. Turn on your kitchen faucet. Water comes out of the tap. Voila! Tap water. The quality of tap water varies by location and might contain traces of minerals specific to the geology of your region, as well as traces of chemicals used in municipal water treatment. Hopefully, your tap water is safe to drink, but that’s not true for as many as 45 million Americans. Filtered water is one solution.
Filtered water starts out as plain tap water. You may already have filtered water in your home by way of a whole-house filtration system, a faucet filter or a water filtration pitcher. Most filtered water passes through some combination of carbon and micron filters, which help to remove chemicals such as chlorine (commonly added to municipal tap water as a disinfectant) and pesticides, and metals like copper or lead. Filters can also eliminate foul odors and tastes.
Purified water usually begins as tap water as well. It will go through many purification processes, including those used for water filtration. Purified water goes a step further than filtering, with a process that removes chemical pollutants, bacteria, fungi and algae. You’ll often find purified water in bottles at your local grocery.
Distilled water is a more specialized type of purified water but much easier and cheaper to produce at home. As with purified water, it meets the classification requirement of 10 parts per million of total dissolved solids, aka contaminants, or less. The process of distilling is simple: Heat tap water to the point that it turns to vapor. When the vapor condenses back to water, it leaves behind any mineral residue. The resulting condensed liquid is distilled water.
Is it safe to drink distilled water?
Making distilled water is like a fun science project.
How to make your own distilled water
Here’s how you can distill your own water at home.
Not to get too scientific here, but this is exciting for me. We’ll be using water in all three of its known states — solid, liquid and gas.
The gist is this: You heat water (liquid), turn it into water vapor (gas), then collect the condensation with the aid of ice (solid). It’s like middle school science class all over again. You’ll likely find everything you need in your kitchen. A large pot with a lid, a small pot, water, ice and oven mitts for handling the hot cookware.
It does take some time for all this science to happen, so be prepared. In my example below, I started with 8 cups of water in the large pot. After 1 hour, I had produced about 1 1/4 cup of distilled water. To create a gallon jug that you’d find in the supermarket you’d need about 13 hours of distilling time.
If you follow these steps, you should get near 100% yield, but whatever amount of distilled water you want to end up with, make sure to add additional water so you don’t end up heating an empty pot(s) at the end of the process, which can damage cookware.
Use caution throughout the process.
4. At this point, you can sit back and wait. I ended up replenishing the ice supply twice within an hour, once at 30 minutes and once after 45 minutes. This is what you need the oven mitts for — that lid will be hot! Use caution when dumping that now-hot melted ice.
