Can Distilled Water Be Boiled?
Yes, all forms of water can be boiled including distilled water. Since distilled water doesn’t have the impurities of other types of water it can be heated past the boiling point (e.g. in a microwave) potentially causing an explosion when you add instant coffee or a similar powder. This is the source of the idea that distilled water doesn’t boil like normal tap water.
Since distilled water is free from most impurities you can expect it to boil at the boiling point of water (100 Degrees Celsius/212 Degrees Fahrenheit). However, when heated in a microwave the lack of impurities can cause the water to heat past the boiling point without bubbling.
This is also called superheating. Then when sugar, instant coffee, or another substance is added microbubbles form causing the superheated water to erupt and explode (see video demonstration below).
How To DIY Distilled Water By Boiling On A Stove
You can also make your own distilled water by boiling tap water then collecting the condensate using a large pot, a small bowl, and turning the lid upside down as shown in this video.
- Put a small bowl or smaller pot inside a larger pot.
- If you want to make super clean distilled water then use distilled water to thoroughly clean the bowl without soap. This will remove any unseen particles attached to the bowl.
- Add water. Don’t add so much that the pot or bowl floats and moves around as it may knock into the side of the larger pot during the steaming process and could break.
- Turn the larger pot lid upside down and place on the larger pot. This works best if you have a glass or clear lid so you can see the process in action.
- Turn on the heat.
- When the water starts to boil add ice to the top of the lid. This will help condense the steam on the underside of the lid and cause it to drop in the bowl.
- Bowl the water for 45 – 60 minutes.
- Add more water around the bowl as the main water level in the pot lowers.
- Repeat until you have a desired amount of distilled water.
Tap water, filtered water, and bottled water all have some minerals which raise the boiling point of water (boiling point elevation) higher than the expected 100 Degrees C.
Is It Safe To Boil Distilled Water?
Yes and no. Yes, it’s safe to boil distilled water. It may heat slightly past the boiling point of water and get superheated but it will eventually start to bubble.
No, it’s not safe to heat distilled water in a microwave and then add a powdered substance like instant coffee, instant oatmeal, or a cocoa package. This could cause an explosion as described above.
There are also some reports that using distilled water in some electric irons could also cause splattering, inconsistent steam, and other dangerous issues due to the same superheating function. Most modern electric irons can run off tap water. Check the manual and use the water recommended.
What Happens If You Boil Distilled Water?
If you boil distilled water in the microwave you can heat it past the boiling point of water and it will not bubble. It will appear as if it isn’t boiling but it’s dangerously heated as described above.
Distilled water boiled on the stove will eventually bubble.
Never added anything to heated distilled water near the boiling point of water (100 Degrees C or 212 Deg F) until it starts to bubble.
Generally it’s safer to use tap water or bottled or filtered water with some remaining minerals in it when you need to boil for cooking, beer brewing, or other purposes.
How Long Do You Boil Tap Water To Make It Distilled?
The instant tap water starts making steam and you capture and condense that steam you are making distilled water. Water will begin steaming slightly before it goes into a full rolling boil. Continue boiling the tap water for 45 minutes to produce distilled water.
Add water as necessary to the boiling water to continue the boiling, steaming, and condensing process. There’s no limit to how long you can boil tap water to make distilled water as long as you monitor it and continue to add water slowly.
You can even pre-heat the tap water in a separate kettle so the newly added water doesn’t stop the boiling process.
Can I Use Boiled Water In Place Of Distilled?
You can use boiled water instead of distilled if you want to make water that is safe to drink by killing any bacteria or viruses in it or to remove chlorine. Boiled water cannot be used instead of distilled water in CPAP machines, engine cooling systems, or refilling batteries.
Boiled water still contains some impurities that could cause scaling or damage to these devices. If you need water that is free of impurities it must be distilled using an electric distiller, non-electric heat based distiller, or purchased in jugs from the store.
Substitutes For Distilled Water
You can use the following substitutes for distilled water for the purposes described below:
- Mineral water – Mineral water is sourced naturally and contains high amounts of dissolved ions making it a form of hard water. Use sparkling mineral water when making cakes, pancakes, or waffles. The sparkling water helps with the rising process. Mineral water is also great for freshwater aquariums for hard-water loving fish.
- Spring Water (local or bottled) – Spring water like mineral water is also naturally sourced but has far fewer dissolved solids and ions. Use this for cooking or as a source of drinking water. Though naturally low in pathogens, most spring water legally must be treated with ozone or similar processes to kill bacteria and viruses before it can be bottled and sold. Do not collect local spring water for use without testing it first for pathogens or sending it through a filter capable or removing harmful viruses, bacteria, and other critters like giardia. Spring water is excellent for fish tanks and brewing coffee and beer. Hardness and pH measurements may be needed and some adjustment required for certain types of beer.
- Bottled Water – This category includes only water sources that have been filtered then bottled. Major water bottle brands simply take tap water, filter it, then bottle it and sell it. Spring water can also be bottled but it comes from natural spring sources and has minimal processing before bottling. Bottled water is excellent for all uses (drinking, aquariums, beer, coffee, etc.).
- Home Filtered Water – Filtering your water at home gives you far great control and allows for the most uses. A simple carbon filter (e.g. Brita) is great for improving taste and removing some impurities like lead and chlorine. It won’t make tap water suitable for CPAPs, humidifiers, or batteries. For that you would need to use a reverse osmosis filter or something similar capable of removing many of the dissolved ions in tap water. When filtered to this level you can use filtered water in place of distilled water.
