Finding the best tankless water heater isn't about having warm water when you need it.
Such a useful product can make or break your day.
Let's go over a scenario to prove my point!
You find out that your kid has also taken a shower for school, and your other kid is finishing his chores from the night before by running the dishwasher. The hot water tank has run out of all the awesome hot water and you don't have 20 minutes or more to wait for it to heat again.
Well, have no fear because the solution is well within reach. Keep reading!
No longer do you have to continue and suffer through having to rinse the shampoo out of your hair as fast as you possibly can while the rest of your body tries to exit the shower to escape the frigid spray; tankless water heaters are here!
What is a tankless water heater?
A tankless water heater is a mountable unit that heats the water as soon as you turn the faucet.
With a series of heating coils powered by electricity or natural gas, the unit accepts cold water and heats it quickly before delivering it piping hot to where you need it to be.
This truly ingenious design doesn't need a 40-50 gallon tank to hold the hot water since it heats it at the site. Because of this, tankless water heaters take up 30-50% less energy than units that have tanks and can save your household around $100 or more per year.
Yearly energy savings and leaving a lighter environmental footprint.
Sounds great, doesn't it?
But are there any possible downsides to having a tankless water heater?
UPDATE: I have published a full post on how these water heaters work.
Makes for a Great Investment
Still, the advantages are plentiful.
The installation investment can be a bit much on your finances, but after just a few years, you'll get a return on your investment for sure.
Is it possible to put a price on the luxury of consistent and ever flowing hot water?
What's a little investment upfront when you can have years of luxurious hot water ahead of you, right?
Below are a few of the tankless water heater models we like best from brands we trust to be dependable and reliable.
The performance of these models is stellar and often backed by a multi-year or lifetime warranties and supported by the best in technological and customer assistance.
Best Tankless Water Heaters: Comparison Table
Our Top Choice
Top Rated across the industry
When you are done reading this in-depth article, we hope you'll have a great start in figuring out the many reasons why you need the best tankless water heater.
Along with that, we'll outfit you with the information you need to make an informed decision about how to purchase the next great addition to your home.
While selecting the best tankless water heater can be difficult, be rest assured that we have mentioned all the factors you need to consider to make a good final buying choice.
You can't go wrong with the promise of the luxury and comfort of sustained hot water.
Normal water heaters will heat water and then store it in 40-50 gallon tanks, keeping it heated for use throughout the house. The way tankless heaters work is by a heating element that heats water as it travels through pipes. Most often this element is triggered by turning on the faucet or some appliance that needs the hot water.
The science behind it is truly ingenious!
EcoSmart has pioneered their models to include a self-modulating technology that allows the unit to self-regulate how much total energy is needed to heat the amount of hot water you'll want to use. Not only does this end up saving you money, but it also lessens the depth of the environmental footprint we all leave.
The units are also compact weighing in at 11lbs, and wall mounted provided valuable storage space to your home. The best part is that each unit comes with an unimpeachable lifetime warranty.
When sized correctly your tankless water heater will provide you with an endless stream of on-demand hot water. We spoke earlier of the climate being a factor and the ECO 27 is ready to meet the challenge of colder weather climates with high flow.
The Smart Technology is meant to operate best in areas where the temperature of the water can be as cool as 37 degrees. At this temperature, the ECO 27 can heat nearly 3 gallons a minute.
There is a digital display panel that allows you to set the temperature in 1-degree increments. This puts, even more, power in the palm of your hand. And that's a pretty awesome achievement.
The ECO 27 is one of the largest tankless water heaters available and is ideal for the northern and southern parts of the United States.
In the north, it can heat nearly 3 gallons a minute, but it can also handle up to a total of two showers running at the same time and never run out of hot water.
In the southern United States where the tepid water runs a bit warmer, the ECO 27 can also take on the high demand of things like hot tubs and Jacuzzis. It can handle up to 6 gallons per minute which is equal to about 4 showers and a sink running all simultaneously without any loss of heat.
The Rheem line of products features a plethora of options meant to fit every lifestyle and budget and the RTGH-95DVLN is no exception, making it one of the best tankless water heaters.
A natural gas option, this tankless water heater provides the comfort and convenience of having a continuous supply of hot water. From homes with busy families to homes with luxury accommodations; if you're looking for a hot water solution, look no further than this Rheem natural gas model.
The unit itself rates 94% energy efficient with its stainless steel condensing heat exchanger. This means upfront savings for you and a lighter environmental footprint.
This is a LO-NOx version which keeps the safety precautions needed when dealing with natural gas in mind. The intelligent electronic controls also help put the task of increasing energy efficiency as well as safety right in the palm of your hand.
Another great feature that stands out in this Rheem natural gas model is that it has a self-diagnostic system which makes installation and service a breeze. The display clearly shows the temperature and any maintenance codes.
The benefits continue with an exclusive Guardian OFW™ Overheat Film Wrap. This helps the unit keep from overheating along with its built-in electric blower.
Furthermore, this unit was built to perform and more importantly, built to last. All of the Rheem water heating products not only meet, but go the extra mile to exceed industry standards in both quality and reliability.
Each phase of the development process is overseen, from raw material delivery to the assembly of the final product. Rheem products are continuously tested and certified by the government and third-party testing labs to ensure they meet the highest of quality standards.
The ECO 27 was an electric model and good for certain environments where such electric products are most often used. However, if your home primarily uses natural gas, then the Rheem RTGH-95DVLN is going to be an amazing fit.
In a normal sized home the Rheem can run 2 showers, 2 sinks plus a dishwasher all at once and still have plenty of hot water left to spare. And with a whopping 9.5 gallons per minute, it's no wonder why.
Additionally, one the water gets hot, it stays hot. There will be no such thing as a "hot water sandwich" where you get hot water for a minute and then it goes cold while the other water is warming. The heating in this unit is continuous, always delivering you fresh, hot water.
The company itself was started in Germany in 1924 by Dr. Theodor Stiebel to create his innovative immersion water heaters.
Since then the company has created a line of heaters meant to fit the needs of several households, and the tankless water heater is key among them. This revolutionary digitally controlled unit holds the distinction of needing no venting unlike some of the others models we discussed.
This can be a great savings on initial installation and upfront costs. Its sleek design fits anywhere meaning you can now make use of the space that used to be taken up by your bulky tank water heater. And you can still save 15 - 20% off of the hot water portion of your electric bill.
Advanced Flow Control
The 208/240 volt Tempra 24 Plus is one of the most technologically advanced tankless water heaters available today!
I mentioned before how Stiebel Eltron keeps evolving to meet the needs of their consumers and this model is a fantastic representation of that tenet.
Completely redesigned from the inside out, the Tempra 24+ has been upgraded with heavy duty electronics to give you a simple single flow sensor design. A hinged cover gives you easy access to the unit and the Tempra Advanced Flow Control™ was created especially for the Tempra to really put the power into your hands.
It is exclusive to the Tempra line of Stiebel Eltron heaters, no other manufacturer of tankless water heaters can lay claim to it. You can set the temperature and be assured of a constant output no matter how many other devices are also using hot water at the same time.
The AFC prevents "hot water sandwiches" or variant temperature fluctuations by automatically adjusting the flow of the water while maintaining its temperature. The SE Tempra 24+ was designed to replace your bulky heated tank system was ease and convenience.
Also, with the electric system, you'll get upfront savings over gas unit installations. I mentioned that no venting system is needed which can definitely save you costs on additional installation or piping, which can be a problem with the Rheem RTGH-95DVLN.
Selecting the right model of EcoSmart heater to use is as easy as 1-2-3!
They provide fantastic and informative guides to assist you in making the correct decision.
As discussed with the ECO 27, EcoSmart has pioneered their models to include a self-modulating technology that allows the unit to self-regulate how much energy is needed to heat the amount of hot water you'll want to use.
Not only does this save you money, but it also lessens the depth of the environmental footprint we all leave. And just like with the ECO 27, this ECO 11 Electric comes with an unimpeachable lifetime warranty for residential use.
You could see savings of up to 60% with this 6.5lb lightweight model and throw away the fears of having to deal with lack of hot water.
For example, in warmer climates the ECO 11 can heat two sinks and one shower simultaneously while in colder climates it can heat two sinks.
The ECO line of EcoSmart tankless water heaters features models that can adapt to any situation.
The ECO 11 is a fantastic, budget-friendly option for those who have smaller living accommodations, but still require the best in water heating.
The ECO 11 delivers every time! 😉
With an energy factor of 0.81 - 0.83, this powerful unit has a max flow rate of 6.6 GPM which makes it ideal for an apartment or small household situation.
It includes easy-to-read thermostats for consistent temperature monitoring ensuring you'll get hot water no matter what is happening outside.
Wherever hot water is needed, Takagi has a unit that will give you hot water with environmentally conscious standards and long lasting value after it's been installed. The makers of this unit take pride in being one of the best tankless water heater manufacturers and their unit proves it on every level.
Since 1952 Takagi has been on the forefront of water heating technology. They've achieved the first in many areas:
- First company to specialize in tankless water heaters in the US
- First to offer a tankless product with unparalleled thermal efficiency up to 95%
- First to offer a direct vent convertible tankless models which allowed consumers to convert the unit to a direct vent unit
- First to use an "air-fuel ratio rod" which acts as a unique safety device
As you can see, they are truly industry leaders. They are just as dedicated to protecting the environment and keeping the world safe and livable for every family.
The T-KJr2 is an easy and convenient experience from installation and setup to final usage. Of course, it's always recommended to get a full survey done prior to installation to make sure it's the right model for you.
But once this is completed, you'll find that often times you can use your existing natural gas life, water lines and vents which already help you save on upfront installation and preparation costs.
There is provided hardware for mounting the Takagi which can used alone or in conjunction with your own hardware. About 90% of the work is getting the unit mounted.
It takes about an hour to make the gas and water connections (always make sure both are completely shut off and empty before starting your work). Once you have it installed, set the temperature to your desired setting and then go test a faucet. You'll see after only a few seconds, you'll have piping hot water at your disposal.
You'll notice the difference immediately!
When you can run the dishwasher, do a load of laundry and have 4 or 5 people taking hot showers simultaneously, you'll wonder why you didn't make the switch to tankless sooner, especially when you see the savings of nearly 30% on your natural gas bill.
Founded in Japan, Rinnai employs over 600 engineers to keep up with introducing the latest technology and environmentally conscious features to their progressive line of products and the Rinnai RL75iN is no exception.
This value added tankless water heater seeks to have a huge positive impact on your home while reducing the negative impact outside of it. The talent and vision of Rinnai is seen in this product which is supported by an uncompromised focus on quality in design and manufacturing.
By utilizing tools like advanced automation and precision assembly, Rinnai is able to guarantee near perfection in duplicate, triplicate and beyond.
All Rinnai factories, in Japan or stateside are ISO 9001 and/or ISO 14001 certified. You can rest easy knowing you're putting only the best in your homes.
The RL75iN is a 10,300 - 180,000 BTU and comes standard with a MC-91-1US Digital Controller that includes a handy Error Code Indicator.
For its size, it maintains a solid 82% thermal efficiency rate and works best within the 98 - 140 degree Fahrenheit scale for residential use.
No fabrics are used and the unit comes with a valve kit for your convenience. Most impressively the RL75iN boasts 7.5 GMP which gives you great hot water flexibility. You can mount it in nearly any room and vent it directly to the outside with a single wall or roof penetration.
At 50 lbs. this is a solid unit, so having the flexibility in size to put it just about anywhere is a real plus. This particular tankless water heater works the way most do with some important distinctions.
Cold water enters the heater from the inlet pipe that rests at the base of the model. As soon as this happens (usually additionally triggered by turning on the faucet or an appliance making a request for hot water), the computer board on the system is signaled to activate the ignition or flame switch.
A combustion fan is activated to allow oxygen into the burner which feeds the flame as the gas control valves come to live, letting a low frequency emit to kindle the fire.
When the fire is adequate, the ignition stops lighting and water is allowed to pass through the pipes to be heated. All of this seems very involved, but it actually takes just a matter of seconds to complete.
Heated water passes through the coils of the copper heat exchange (copper is a great conductor) and then travels out of the top of the unit and to the place which requested the hot water. There are also "condensing" models available wherein the water is preheated as it passes through a stainless exchanger and the heat is captured before it's vented out.
The awesome thing about the Rinnai is that the gas valve and blower automatically adjust the gas and oxygen used to heat the water based on the demand.
If you're just running a couple of showers and a faucet then the RL75iN will use a smaller flame and less gas. If you need more heat, the Rinnai senses this and spreads the fire along the ingeniously designed system to heat more of the water at once.
Additionally, when the appliance that requested the hot water has finished being in use, the cold water stops entering the tank and the flame simply goes out. The combustion fan operates at low speed for a short time to ensure proper venting. But the unit itself goes into rest mode until the next request is made.
This allows the amount of gas to be used, the only amount that's needed. You'll see great savings the next time your gas and water bill show up.
The Mary Power Gas 10L tankless water heater with digital panel delivers nearly endless hot water with optimal energy efficiency. This unit is unique in that no outside electricity (outside of 2 D-cell batteries) is needed.
This saves you on tons of costs to upgrading your electric system and also lowers your bills over time. Additionally, the design of the Marey makes it so it only uses gas when heating up the water.
The energy efficiency can range from 54 - 87%. This means incredible savings for your home while still guaranteeing your household unparalleled performance.
The unit is simple to install and includes the same kind of auto ignition we've mentioned in the other models present in the best tankless water heaters reviews list that signals the unit to begin heating the water.
There are adjustable water and gas nozzles so you can control exactly how much output you get and all of the information can be viewed on an easy-to-read digital display. The batteries fuel the electric pulse ignition so you don't have to worry about the lights flickering whenever someone turns on the faucet for hot water, which is something that the EcoSmart ECO 27 (Electric) lacked.
The Marey is rust proof so you'll get no water leaks due to leaks. The units also have anti-combustion and gas pressure safety protection which ensures the safety of your home and loved ones while the unit is in use.
It works easily with low levels of water pressure and output can reach a solid 3.1 gallons per minute. It's a lightweight at 21 lbs. but still packs a lot of power into a small amount of space.
Founded in 1955 by Mariano Reyes, Marey was a company that was literally built on the Reyes name (MAriano REYes). From the very beginning Mariano took ownership of his products and stood by them proudly.
He worked hard to learn about the production and innovation of tankless water heaters and developed the point of use shower water heater. Building this invention into a market leader in his home of Puerto Rico, Mariano made Marey a household name and one that is synonymous with quality, safety and efficiency.
The company specializes in providing reliable products at prices that are affordable by all. As the industry changed and more demands were made for on-demand water heaters that safely used gas.
Marey stepped up to the plate and truly delivered with the Power Gas 10L model. Anywhere hot water is needed, there is a Marey nearby ready to step up to the challenge.
The benefit of this system is that such a lightweight box that barely takes up any room can outperform a unit twice or three times its size. And it can do so with using the minimum amount of energy.
This unit is dedicated to being environmentally friendly and making the world a cleaner and healthier place to live for family all over. They make it their priority to produce the highest quality, most eco-friendly and affordable tankless products on the market today.
The goal of reducing the strain of global warming, and CO2 emissions are just two of the things the company does to lessen the weight of their environmental footprint, and those values are then passed on to you.
Choosing to put a Marey into your home is choosing to care about the world around you. Another feature of this handy machine is that because of its size, the unit only uses a ½" gas line. This is standard for many places so additional construction won't have to be done; you can simply use your existing gas lines.
The Marey units are sensitive so it takes only a little bit of water to ignite them, but most times this is not a problem. Simply open your faucets to full power while the water heats up.
Once it warms, edge the faucet back to your desired temperature. This helps maintain the unit. For consistent, hot water in a smaller home, the Marey is an incomparable tool that works with such ease and convenience; it doesn't take a professional to install.
And if you do need assistance, their customer service is renowned for giving excellent guidance to solve any issue.
Now that you've seen a good selection of the best tankless water heaters, we'll discuss how to decide which one is perfect for you and your household.
There are several factors to consider and we'll go over each one to help you make the most of your new investment!
Tankless Water Heaters Buyer's Guide
Location, Location, Location
Where you live is the first thing to consider when figuring out what kind of tankless water heater to get. It may seem strange, but it makes more sense when you consider that the water is of naturally different temperatures in different parts of the country.
More northern states and territories have colder water than their southern counterparts. What this will affect is the rate and efficiency with which your unit will heat the water. So, if you live in a colder climate, your unit will produce lesser gallons per minute than in warmer climates.
Most tankless water heaters have systems in place so this won't negatively affect you, which is why it's important to get a tankless water heater that's calibrated to the area in which you live.
Check a water temperature map for the area you plan to have your new water heater. Determine what your average inlet temperature is as this will allow you to assess how many applications your unit will be able to run simultaneously at your chosen temperature.
One machine's performance can vary greatly depending on its location, and rate of usage. Once you determine the model make sure your electrical infrastructure is correct and sound for your unit. It'd be a shame to purchase a model that needs more power than your current system allows.
The Old House
Some houses have older and outdated plumbing and electrical systems that may not be the best to work organically with your new water heater.
It's recommended (and sometimes required by the warranty) to have a professional come and inspect the area where you plan to have the heater in order to make sure it will be able to support the new system.
Each tankless water heater comes with a detailed installation guide that tells you exactly what your specs need to be to use your unit to its full potential.
All About the Flow
Good flow is paramount to figuring out which tankless water heater is going to be the best for you. Flow rate has to do with how many gallons per minute each application in your home is requesting at any given time.
For example, you want to run a faucet to fill up a sink to wash some dishes at a flow rate of about .75 GPM (gallons per minute). At the same time, your husband or wife wants to take a shower at a rate of 2.6 GMP.
Your optimal water heater would need to have a flow rate of at least 3.26 GMP to efficiently accommodate both applications.
It's easy enough to determine your flow rate, especially if you have a bucket and a milk jug handy. Simply fill the milk jug and pour it into your bucket.
This will determine where on your bucket the gallon fill line in, mark this for use later. Then take the bucket to the application you wish to test and using a stopwatch, time out home many times you reach the gallon line in your bucket in a minute.
This will be the flow rate for your application. The higher the flow rate, the higher the flow rate your unit will need to have to maintain those applications running simultaneous. A good solution for this is to install flow regulators or just install low flow appliances.
Gas or Electric?
When deciding on a new model, figuring out the chemical makeup is just as necessary as flow rate. Deciding between electric and gas can mean savings in setup and installation and the safety of your unit as you run it through its lifetime.
Electric tankless water heaters are 99% efficient, but many don't qualify for costs saving rebates or an Energy Star rating which can add value to your home though they usually include cheaper installation and a longer service life.
According to the Department of Energy, natural gas models are about 23% more efficient than tank models making them about 60% efficient overall. Although this is less efficient than electric models, gas is more abundant and typically a cheaper fuel. Often natural gas models quality for a $300 federal tax rebate available in kind in many states.
Really it comes down to your comfort level. Once installed, both units will run approximately the same with negligible differences putting one over the other.
All in all, buying the best tankless water heater can be the top environmental investment in your home that delivers benefits to the earth and you.
Lower utility costs, more space and consistent hot water at your fingertips are just some of the reasons why getting a tankless water heater will be a great option for you.
I'm confident that with the tankless water heater reviews above, you now have the tools to make an informed and conscious decision that will only add value to your home. If one were to choose, as stated, the EcoSmart ECO 27 (Electric) is our choice and happens to be the best for the money.
Go ahead and check out some of the included links today. You'll be glad you did.