Drink From a Water Heater

Is it Safe to Drink from a Water Heater?

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Whether it’s a situation of survival or whether you’re just too lazy to heat up the water in a kettle for your tea (fair enough—why expend the extra energy when your stove or microwave is giving you perfectly hot water?), there are a range of reasons for wanting to drink from a water heater if it is full and you are low on, or out of, water in a tight situation. It’s simple, it’s convenient, it’s effective—all you have to do is open the drain tap on the bottom of your water heater and have the hot or cold water will flow into the container of your choice.

However, is this healthy, or even recommended? Depending on the water quality in your area, it can generally be assumed that that water from a heater should be able to be used for cooking or drinking. It does pay to be a bit careful in you are stuck in a distant or strange area, and don’t know the water quality. If that is the case, it would be good for you to know what can make hot water from a heaterharmful, anyway?

Here’s the our research and digging around on the subject matter presented to you! Read on!

Why Water from the Heater May Be Harmful

All water, for it to be consumed, should be of certain quality and have certain characteristics. This quality is maintained by your local health department and your water supplier or distributor—which have both a moral obligation and a legal need to ensure good water quality.

So, if the water flowing into your system is tested and guaranteed to be of the required quality, where does the harm happen? It could be faulty plumbing, especially if the material of the pipes is old and outdated. More commonly, though, there are two reasons that can affect the quality of water in your house—high temperatures and staleness.


Water, when left for more than 4 hours, especially in your pipes, qualifies as stale. These 4 hours give the water enough time to possibly get infiltrated by impurities, contaminants, toxic gases and so on, due to its contact with the pipe and other materials through its journey. Even if you do clean your tank out regularly, the material of your pipes may still pose a threat to the water, especially depending on how old or new they are. The same applies to water in your water heater tank.

Additionally, plastic pipes are a hotbed for germs. Therefore, in addition to the contaminants in the water, bacteria and germs are also a very real threat. One of the most common and “popular” threats is Legionnaires’ disease, a type of pneumonia. Just as misunderstood as it is popular, Legionnaires’ disease is caused by Legionella—a family of minuscule, rod-shaped bacteria that are able to procreate in stagnant water only.

While nobody wants bacteria in their water at any cost, Legionella is commonly present in water and drinking or washing your hands with water that has these bacteria holidaying in them presents very minimal risk of infection and the occurrence of a notifiable disease is very rare. Legionella generally causes diseases only when it’s inhaled with contaminated water vapor.

Don’t worry—you don’t have to resign yourself to ingesting large amounts of Legionella. These bacteria are killed when water hits 60 degrees Celsius, which, incidentally, is the ideal, prescribed temperature for storing hot water in residential buildings. This means that if you have Legionella in your water, it’s only because the water was left for too long in the pipes.

High Temperatures

If storing water in your tank for over 4 hours is Homelander, storing heated water in your tank for over 4 hours is Victoria Neuman (spoiler alert, but if you haven’t watched it already—come on!). Heat only worsens the situation significantly, making it super easy for metals to migrate into the water. As the temperature increases, so does the solubility level of the metals—lead, for example, dissolves two times quicker at 77 degrees Fahrenheit than 59.

Similarly, there are tons of other toxic metals in your plumbing, pipes, fixtures, fittings and so on, that aren’t toxic on their own in the cold, but are definitely to be stayed away from as temperatures rise. These include galvanized iron, plastic, copper and stainless steel and it can take as little as one night for the amounts of nickel, lead and copper to far exceed the healthy, recommended levels in the water.

Another very common problem that results in water-quality issues has its roots in the water tank and the impact of hot water on it—heated water corrodes your water tank and pipes. This corrosion can adversely affect the taste, smell and color of the water flowing through.

If the interiors of your tank contain plastic, a material that has a very low tolerance to heat, you may even find small bits of plastic in the water, in addition to a foul smell and a slimy feel, like water in stagnating ponds. Remember, various parts of your hot water tank have a plastic composition, from the TPR valves to the dip tube to the temperature gauge and plastic, as we all know, isn’t very durable, despite its insane ability to remain on the face of the Earth for millions of years.

So Do I Bid Warm Tap Water Adieu?

Not at all. Warm water is healthy for the human body and recommended. Heating water on your own may make it too hot and disturbing for your body—it’s the same with cold water. Your organs, especially your intestines and stomach, need to expend extra energy to adjust the temperature of the water, gushing towards and passing through them, to the temperature of your body. Therefore, your body may end up spending more energy than it is absorbing from the water. Somehow, warm tap water is the ideal temperature or the closest to it.

So how do you ensure that the tap water you’re drinking from the heater is safe on all counts? If I’ve said it before and I’m saying it again, it’s only because it bears repeating—regular maintenance. With regular maintenance (flushing the tank, checking the temperature of the tank and the pressure relief valve and checking the anode rod), you can avoid a ton of water issues. Follow the manufacturer’s recommendations on this and if there aren’t any (or you’ve lost them), stick to yearly maintenance.

Proper maintenance will slow down the rate of internal corrosion. Flushing your tank will get rid of any accumulation of corroded materials resting at the tank’s bottom, failing which, these may enter your hot water pipes and lend a rust color to your water. Flushing will also let your tank operate more efficiently, letting the water hit higher temperatures faster.

Don’t forget to check the burners. If the water-heating burners are layered with sediment, they won’t be able to heat the water enough to bring it to higher temperatures. This can also cause bacterial growth in the tank and result in rotten-egg-smell-emitting water.

You can also minimize your water issues by doing the following:

  • Let’s start with an easy, obvious one—boil the water! As you know (or should, if you paid any attention in school), boiling water gets rid of germs and bacteria.
  • Minimize risk by monitoring water quality. Get your water tested at the local laboratory so you know what’s inside it. The folks at the lab will also tell you what the composition of your water means for you and how you can better it.
  • If you’re worried about stale water, run the tap for at least 30 seconds so that you get rid of the bulk of the stale water cache.
  • If your pipes and plumbing are old and require maintenance or even replacement, do it (you don’t need to and shouldn’t wait, till your pipes are visibly falling apart to do so). Get a plumber to inspect the system.
  • Consider making some other structural changes to your plumbing, like replacing the original valve, on your water heater, with a ball-valve drain assembly. These, unlike factory valves, come with a straight path sans any small orifices, so there’s a lower chance of sediment build up clogging the hard-water areas and restricting water flow.
  • A super-simple way to greatly minimize the risk of water staleness is to get a tankless water heater. These are safer than the ones with storage tanks; however, the threat of the pipes and other parts coming into contact with the water and contaminating it, still exists.
  • Never and I repeat, never, use water from the heater to prepare food or infant formula for toddlers. Additionally, people who are immunocompromised, small children and babies shouldn’t drink water from the heater.

The Final Word

Ultimately, though, the hard truth is that water from the heater is not safe to drink. It may take longer, but it is completely worth the effort to take the water from your heater, heat it as much as you want and then use it for drinking or cooking. Use cold water for the above process—in case the water feels warm, let it run for till you can feel fresh, cool water flowing again. Remember, health and remaining healthy must be prioritized over everything else and you shouldn’t just rely on your local water distributor or the government to do it. So get off that couch and go ensure that you’re giving your body the healthiest water available!