The Benefits of Tankless Water Heaters

The Benefits of Tankless Water Heaters

Tankless water heaters are more common than they used to be, but they still haven’t overtaken traditional tank-style heaters in widespread use. Many consumers aren’t quite sure how they work and because of this, they’re hesitant to buy one. You may wonder if they can really keep up with your water demands or if they can get the water as warm as your current water heater can. After all, if you’re not sure about how a tankless water heater performs, then you’re certainly not likely to buy one.

In general, tankless heaters perform about as well as standard water heaters and actually manage to avoid some of the problems that you’d encounter with traditional tanks. Let’s look at some of the benefits these heaters offer so you can decide whether a tankless water heater is right for your home.

There’s Always Hot Water

One of the biggest problems with traditional water heaters is that you only have as much hot water as the heater’s tank can hold. If you’re using a lot of water for dishes, laundry, baths and everything else, you can run out of hot water and be left with water that’s warm at best and possibly just straight cold. When this happens, you have to stop everything and wait for the tank to fill back up – then wait for all of that water to heat up.

Tankless heaters avoid this issue by heating water as it’s used. A water pipe passes through the heater, the water in the pipe is quickly warmed to the temperature you set and once you’re done using water no additional water is heated.

It Can Save You Money

That bit about tankless heaters only heating up water as you’re using it is very important. Traditional heaters have to keep an entire tank full of water heated up in case you need it, while tankless heaters only heat the water that you’re actually using. This uses significantly less energy and that can lead to some very significant energy savings in the long run.

There may be additional savings involved as well, since tankless water heaters are often designed to be more energy efficient than their tanked counterparts in general. This means that you not only have less active usage, but that active usage requires less energy to heat as well.

It Requires Less Maintenance

A typical water heater essentially contains two heating elements and a thermostat that controls them. This allows the water in the tank to have approximately the same temperature throughout – so long as none of these parts are working properly. If (and when) they fail, you’ll have to deal with lower water temperatures and the cost of replacing one or more components to get the heater back to normal operation. Additional costs may be incurred if you have your water heater tank cleaned to remove sediment, along with the inconvenience of not having hot water until it refills and reheats.

Tankless heaters have fewer parts to maintain and no tank to collect sediment. Instead of two separate heating elements, you have a single heater unit that isn’t constantly in use.

It Takes Up Less Space

One of the big drawbacks of traditional water heaters is that they’re big. The more hot water you want available, the bigger the tank has to be and the more room it takes up. This means that there’s going to be some spot in your house with a large tank sitting in it, possibly using up space that might otherwise be used for storage or other purposes.

You don’t have this problem with tankless heaters as they are typically wall mounted and have a very small footprint. All you need is enough room for the heater unit and the pipes leading into it, freeing up potentially valuable storage space and giving you many more options on where to position your heater.

It Prevents Ruptures and Leaks

One of the worst things that can happen with a hot water heater is to get a major leak or rupture. Given how much water one of those tanks can hold, you don’t want it all spilling out onto your floor or into your basement or crawlspace. If you’re not home when it happens, you might have even bigger problems since the water will still be running and trying to refill the leaking tank.

Tankless water heaters avoid this problem by simply not having a tank to rupture. You can still have a leak in one of the pipes entering or leaving the heater, but you’ll have a lot less water coming out of a small pipe than you would a large tank. More importantly, it’s easier to fix a pipe than a water heater tank.


  • Allen Sampson November 27, 2015 at 10:56 pm

    where can one get more info on the tankless water heaters, thanks,,

    • Eddy Mills November 29, 2015 at 10:15 am

      We carry a wide variety of tankless units to choose from.

  • Frazer Strowbridge November 29, 2015 at 7:07 pm

    I was also wondering where I could buy and have this installed and as well the price of such. TKS

    • Bill Keiser December 7, 2015 at 10:51 am

      Cost would vary wildly. Main parts for mine:
      – 12kw heater $300
      – service valve set – $80
      – Mixer $100
      – 3M Aquapure water treatment to reduce water hardness $70
      – misc fittings, tubing, about $100
      I was able to do my own labor, but:
      – a 220v high power service to each heater is required.
      – If you have a traditional tank heater, your plumbing will have to be modified at each heater location.
      I suspect total cost with labor would be around at least a thousand dollars.

  • m.s.Woods December 5, 2015 at 6:10 am

    I have two tankless water heaters on my home. They work great for the bathrooms and showers that are close to the heater by way of pipes. Unfortunately it takes 1.5 minutes for warm water to reach my kitchen. It is never hot.

    • Dan December 7, 2015 at 11:30 am

      Install a re-circulating pump and valves at each point of use. Relatively inexpensive and works great to ensure hot water is where you need it/when you need it.

  • Rick Wilson December 7, 2015 at 8:41 am

    I would like to know what brand of heater users recommend.

  • Kay Thrasher December 7, 2015 at 9:09 am

    I’d love to know the bias of whoever posted this article; it reads like someone who might sell tankless heaters. I work for an engineering company and I do specify these heaters. However, there are some very important issues with them; such as, what is your water flow at the fixture? If you have a new shower head that only flows 1.6 GPM (that’s mixed water temperature) and your heater doesn’t turn on unless you flow 1 GPM you may have to take either really hot or cold showers.
    The article also makes it seem that they are ‘no maintenance’ – we have had some issues with them as some of them have more electronic controls than conventional tank-type heaters. Most water heaters do not require much maintenance (draining once a year) and both tankless and tank type electric have the same issues with elements.

    Make sure that you do your research on what is appropriate for your use before you spend premium dollars for a tankless heater. I considered one a couple of years ago when I replaced my heater; a standard tank type met my needs better.

  • Bill Keiser December 7, 2015 at 9:35 am

    Unfortunately, I know far more about plumbing than I ever wanted to! We’re on our second set of tankless heaters. This is what I’ve learned in the process:
    – Go more powerful than you think you need. We have 12 kw(220VAC 50 amp)units on our bathroom and kitchen(sink, dishwasher guest shower and washer.)
    – Inspect the circuit diagram before you buy. Both sides of the element power should be switched. Otherwise, the element can short to ground halfway through the pipe and go full on with no flow, resulting in superheated water and live steam spraying out of your faucet. (Examples: Bosch Powerstar has one side connected to power with no safety. Stiebel Elton has both sides switched with a relay.)
    The heater you choose should have as low a turn on rate as possible. One with a higher rate can turn off if the flow is a trickle(especially if you use a mixer, which tends to have a lower flow because it is mixing in cold) Typical turn on rates are .5 to .7 gpm. The Stiebel digital models have a turn on rate of .26 gpm. (It’s not pleasant to have your shower either scalding hot or ice cold with nothing in between!)
    – Install maintenance valves . These allow the water to be shut off, a pump connected to pump cleaning fluid (basically vinegar) to remove deposits. (deposits can clog the heating chamber, decrease heating efficiency, and cause corrosion and shorting.
    – Add a mixer valve. Tankless heaters tend to have fluctuating temperatures. With a mixer, you can set your heater temperature higher(typically 140F). This goes to the mixer that mixes cold water with it to hold an exact temperature, and never goes above it. (We keep our kitchen sink at 107F) Our old heater had to be adjusted at least twice a year because of ambient temperature changes from summer to winter. A mixer makes this unnecessary.
    – Whole house models replace a single traditional tank heater, but you still have to wait for the heat to reach the faucet. Smaller units mounted at bathroom, kitchen, etc. will deliver hot water within seconds. The smaller units are less expensive per unit, but have to be wired with 220v 40 or 50 amp service.
    – They are small, but do require space near the faucet. We were able to install ours in the crawl space directly under the floor. With service valves, mixer and plumbing, it fills up about a 2 x 2 x 1 foot space.
    – I’ve heard good things about natural gas models, but don’t have gas.
    – Tankless heaters hold less water than a tank heater, but if either ruptures, they are going to leak out as long as the water is connected. Either kind of heater should be mounted where leaks will not cause problems. Either outside, in a room with drains or with a drain pan under it that drains outside.

    • Mark H December 7, 2015 at 10:02 am

      Thanks, Bill— that’s the type of information that the original article should’ve had!

  • Bill Keiser December 7, 2015 at 9:50 am

    Most tankless heaters do not specify a GFCI breaker. But if our first tankless heater had had a GFCI, it would have tripped and not allowed hot live steam to spew out of my kitchen faucet.
    The new Stiebel I have has a dual thermal emergency shutoff that switches both legs of the power. The old Bosch did not.)

  • Pete December 7, 2015 at 10:54 am

    A couple of other points not covered in the article (FYI, not a plumber but a home DIYer who spec’d and installed a tankless a few years ago)…

    1) Tankless systems can be setup as either “Whole house” solutions, or “Point of use”. A whole house is exactly as it sounds… replace your old tank heater with one big tankless heater to serve the whole house. You will get a delay in the hot water to your tap due to time for the heater to fire up plus get through the pipes, but install is easier and cost lower. A point of use system is where you put multiple small tankless heaters every place you use hot water. Great for a new builds, since you only have to run cold water lines and the delay for hot water is much shorter; better than with a tanked heater, even. More time to install, takes up space near the point of use and higher total install costs are downsides.

    2) Flow rates: With tank systems, you are limited in the total amount of hot water you get before you have to wait for the tank to refill and reheat. But you can pull that water as fast as you want, the heater doesn’t care. With tankless, it will keep making hot water all day, but it can only make so much at a time. That means your flow will be restricted by how much you want to do at once. The bigger the heater, the more water it can put out at once. Try to pull more than that and your nice high pressure shower head will barely be dribbling out the hot stuff. And if you undersize your heater, you’ll be cursing your unfulfilling shower for years.

    3) Electric vs Nat Gas (or LPG): If you are trying to go all electric, there are plenty of heater options, but you are going to be limited in size. A bigger home running a whole-house system is going to struggle finding the flow rates in electric units to service the house. There are some brands that allow you to chain multiple heaters together, but you better make sure you have plenty of available electric service in your panel. If you are going Nat Gas or Propane, however, the options open up significantly. And the only electric needed is a simple 110vac circuit for controls.

    4) Maintenance: These units do require some upkeep by descaling the system, especially if you have hard water. Really, it is just about keeping the pipes clear and open without any restrict. Plan on doing this annually. BUT some electric heaters can’t handle the descaling process (could significantly damage electric heat elements). Those electric units pretty much have to get thrown out if they accumulate too much scaling internally.

    All that said, I was thrilled to have installed our tankless heater and would do it again. And in an industrial plant, we install point of use systems all over the place because they are so efficient and easy to install.

  • Bill Keiser December 7, 2015 at 11:02 am

    Hard water – If your water supply is above 11 “grains per gallon”, you should probably do something about softening your water. A home water softener can be a couple thousand dollars or so. Yearly maintenance of pumping vinegar can help. I compromised with the service valves an a 3M Aquapure cartridge that claims to reduce hardness. The unit was about $60, replacement cartridges are about $30 each. I think they recommend changing the cartridges twice a year, but I think you can monitor the water with a handheld TDS meter and get more mileage from them.

  • Mark Radell December 7, 2015 at 12:24 pm

    How do recirculating systems work with Tankless Systems? We have a small circulating pump attached our hot water system so we don’t have to wait for hot water in our master bathroom suite. We’d love to have this keep working when we install a tankless system.

  • Tom December 9, 2015 at 3:43 pm

    Quote: “When this happens, you have to stop everything and wait for the tank to fill back up – then wait for all of that water to heat up.” :Un-Quote

    The author has almost no understanding of plumbing and water flow. You never need to “wait for the tank to fill up” when using a standard water heater. It’s constantly replenished from the cold line going in the top.


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