Back in the days, water heaters were mainly heating systems with high capacity tanks that took up much space. Nowadays, thanks to technology, we now have tankless units that provide hot water on demand.
Although they cost more initially, tankless water heaters offer a lot of benefits over regular tank systems.
Apart from saving you a lot of space, they have a higher energy efficiency, which makes them a more economical choice. You only pay for what you use and never run out of hot water.
Since more households are making the transition to tankless units, the market for these heaters continues to expand. As a result, it is hard to know which models are worth your money. But not to worry, we are here to help you out.
After doing all the leg work, we’ve finally compiled a list of the best on demand water heater in the market. Whether you’re looking for a unit to serve you alone or one to meet the needs of a big family, you will definitely find something here for you.
Editor’s Recommendation: Top 5 on Demand Water Heater
Things to Consider Before Buying
As earlier indicated, buying a tankless water heater is a big decision. There are certain things you need to consider when searching for a model to suit your needs. Let’s quickly look at them.
One of the key things to look out for when choosing a tankless water heater is the flow rate. This is a measure of the amount of water the system supplies. And it’s usually expressed in GPM (gallons per minute).
The number of devices or discharge points should determine what flow rate you should go for. For instance, if you plan to supply hot water to just one faucet, then a unit with 1-2 GPM should be adequate.
However, for large family households, you will need something higher to support multiple faucets at once. Such units are usually larger in size.
Tankless water heaters may either be powered by gas or electricity. You can go for any one of these units depending on the power source in your resident. If you have a gas supply, then you might consider purchasing a gas unit. Or else you can purchase an electric unit.
Generally, any one of these systems is more efficient than a tank unit. So feel free to choose either one of them, depending on the power source in your home.
As earlier indicated, you can save more money by installing a tankless water heater instead of a regular unit. And this is simply because tankless systems consume less energy.
However, the total amount you save in the long run depends on the energy factor of the individual unit. The energy factor may be expressed in decimal (0 – 1) or in percentage (0-100%). Moreover, the higher the efficiency, the better, although models with higher efficiency tend to be more expensive.
In addition to a high energy factor, we strongly advise going for a unit that has Energy Star certification or some other relevant certification.
A good way to shop wisely when purchasing any device is to buy from a reputable brand. This gives you a better assurance of quality and performance.
In the world of water heaters, some of the well-respected brands include Rinnai, Ecosmart, Stiebel Eltron, Rheem, and Noritz.
5 Best on Demand Water Heater Reviews
Below is a detailed review of the five best in the market.
1. EcoSmart ECO 27 Electric Tankless Water Heater
- Savings of up to 50% on water heating costs....
- Digital temperature control in 1-degree...
- Copper and stainless components designed for...
- Compact size saves valuable storage space,...
- Prior to purchase & installation, please...
Water heating requires energy, which is why there’s so much emphasis on choosing an efficient unit. On-demand water heaters are designed to consume less energy, thus helping you save on your energy bills.
The EcoSmart ECO 27 Electric Tankless Water Heater is a perfect example of a heating unit that does this pretty well.
With the ability to save up to 50 percent on your water heating cost, this tankless water heater is one of the most efficient systems out there. And we have its self-modulating technology to thank for this.
Apart from its high efficiency, the heater flourishes in simplicity and user-friendliness, which makes it a good option if it is your first time to go tankless.
The unit is highly reviewed with a lot of positive ratings. This should give you an indication of what to expect in terms of its quality and performance. Many users consider this to be the best tankless water heater electric unit out there, and it’s not difficult to see why.
This heater has a compact space-saving design, which makes it suitable for homes with limited spaces. Temperature adjustment is done in 1-degree increments via a digital control which is intuitive and simple to use.
The parts are made of copper and stainless steel, which makes them highly durable and efficient. Most of the parts can be easily replaced.
With this unit you get a flow rate up to 3 – 6 GPM depending on the temperature in your area. This makes it sufficient for small to medium-sized families. At 6 GPM, you can have up to four showers or faucets running at the same time.
Overall, this is a good looking heater that will definitely help you save on your energy bills. We highly recommend it!
- Durable construction
- Easy to install
- Compact design
- Features digital control for temperature
- High energy saving
- Flow is lower in colder climates
2. Tempra 24 Plus Whole House Tankless Electric Water Heater
- Digital temperature control. Voltage : 240...
- Proven reliability
- No venting required
- Sleek design fits anywhere
- Save at least 15-20% on the hot water portion...
Electric tankless heaters are notorious for being highly energy-efficient and easy to install. But this high efficiency may affect their ability to meet higher demands. Luckily, some electric units defy the odds; the Tempra 24 Plus by Stiebel Eltron is definitely one of them.
With up to 4.68 GPM flow rate, the Tempra 24 Plus competes favorably with a lot of gas-powered units out there. So if you’re looking for a heater to support 2 or 3 bathroom or faucets, you will not be disappointed with this one.
The first thing you will notice about this heater is its small and compact design. In fact, it has the size of a briefcase, making it installable almost anywhere. It is a perfect choice for cabins and small houses or anywhere with very limited space.
Moreover, the heater is also quiet and doesn’t require venting for installation. This should come as a relief, especially if you’re planning to install the unit by yourself.
The quiet operation of the heater is mainly due to the use of high-quality components that don’t vibrate as well as the absence of mechanical switches that may cause any disturbance.
So you are left with a water heater that operates silently without any form of disturbance. This is obviously a major highlight of the unit compared to many similar models in the same category.
Cold burst a common problem with most tankless heaters, especially when there’s high demand. Luckily, this is not the case with the Tempra 24 Plus. Thanks to its advanced flow control technology, the unit is able to automatically adjust itself to supply hot water at the same temperature during periods of high demand.
The heater also comes with a self-regulating thermostat that helps you to modulate temperature and flow in case you don’t want to use manual controls.
Like the previous model, this one also features a self-modulating technology, which makes it more energy efficient.
- Sleek design
- Doesn’t require venting
- Advanced control technology
- Not ideal for large homes with 4 or more bathrooms
3. Rinnai RUC98iN Ultra Series Indoor Tankless Water Heater
- INDOOR installation only. Fuel Type: NATURAL...
- Concentric or PVC venting option
- Up to 0.96 Energy Factor/Up to 0.92 Uniform...
- The space-saving design allows Indoor...
- Ultra low NOx emissions
The Rinnai RUC98iN is a perfect example of an on-demand water heater that is not only energy efficient but also has a lower running cost. If you want to save extra (more than you would with an average tankless unit), then this is the heater to go for. But mind you, it has a high price point.
Rinnai runs on natural gas, which is why it lowers your energy bills even more.
Unfortunately, the most common problem a lot of people have with natural gas heaters is that they require venting. But the RUC98iN tries to make things easier by offering you two venting options – concentric venting and PVC.
So you can choose any one of these that is most convenient for you. Isolation valves are also included to make routine maintenance easier.
In terms of flow, you get as high as 9.8 GPM with this unit. There are very few units that go higher. This makes the heater ideal for supplying hot water in large homes where there might need to support multiple faucets at the same time.
The unit supports only indoor installation and requires venting. However, you are given two venting options – PVC and concentric. So you can choose the one that is most convenient for you.
Furthermore, the heater has an energy factor of 0.95, which is one of the highest you can get. This ensures you save significantly on your energy bills.
The major downsides we found with this unit is that it’s heavy. Also, since it’s requires venting, you may find it difficult to install if you choose to do it on your own.
Notwithstanding, this is still a great tankless model and, without a doubt a top contender for the best on demand water heater. It is highly recommended.
- High flow rate
- Very energy efficiency
- Recirculation capability
- Eco-friendly (Extremely low NOX emission)
- Supports Wi-Fi
4. Rheem 240V RTEX-13 Residential Tankless Water Heater
- External adjustable digital thermostatic...
- Durable Copper immersion two heating...
- Simple installation – 1/2 NPT adapters...
- 99.8% energy efficient. External controls to...
- Threaded for easy replacement, simple...
Another tankless heater that comes highly rated by users is the Rheem RTEX-13. Built with simplicity in mind, this unit is one of the best deals you can get for meeting hot water demand in your home.
According to the manufacturers, the heater offers up to 99.8 percent energy efficiency, which is very impressive. There are very few units that are nearly as efficient.
So if you want to see a significant drop in your energy bills, then this is the heater to go for. To be more specific, you can save up to 30 percent on your electric bills every single month. So you should get back your initial investment in the first year.
Installation is also easy; even non-professionals can do it.
Strangely, there’s no energy star rating on the unit yet. We don’t know what is holding back Rheem, but we can brag about the system any day.
The inclusion of a digital control panel ensures the system doesn’t overheat. You also have the portion to connect another tankless heater to the system whenever there’s a high demand for hot water – thanks to its EZ link cable.
With the ability to supply hot water at 9.5 GPM, this is definitely the kind of heater you want to install in a large household. Like most high-end models, the system also uses self-modulating technology for improved efficiency.
- Digital control
- Compact design
- Affordable price
- Easy to install
- Not very durable
5. Rheem RTGH-95DVLN Tankless Natural Gas Water Heater
- 94-Percent Energy efficient with...
- Intelligent electronic controls designed to...
- Third party efficiency listed by AHRI
- Up to 38-Feet of 3-Inch PVC Pipe or 5-Feet of...
- Low Nox Version
If you’re looking for a high performing tankless heater and don’t mind paying extra for it, then the Rheem RTGH-95DVLN would make a great choice.
This is one of the few units that is built to offer all the core functionalities you might expect from an on-demand heater while also delivering huge water supply to meet the needs of whole households.
The problem with most large capacity models is that their high flow rates usually come at the expense of temperature regulation. It is normal to experience temperature fluctuations with these systems whenever there’s high water demand.
Luckily, this is not the case with this Rheem heater, and we have its highly efficient stainless steel condensing heat exchanger to thank for this. You have the option to connect the vents to meet high water demands while still maintaining uniform temperature.
The system also includes various electronic controls to ensure safe operation and increased efficiency. With this heater, you get up to 94 percent energy efficiency, which is quite impressive.
In addition, the unit has very low NOX emission, which makes it safe for the environment.
- Works 8,400 ft. above sea level
- High flow rate
- EZ-Link connectivity
- Low emissions
How to Use a Water Heater?
Even though they are energy efficient, water heaters usually have a high upfront cost, which makes them very costly to replace. As a result, in order to get the most out of them, it’s very important you know how to use them.
Follow the tips below to use your heater for optimum performance and longer lifespan.
Reduce the Heater Temperature to Cut Costs
The set temperature for most water heaters is usually 140 degrees Fahrenheit. However, you can still reduce the temperature to 120 degrees Fahrenheit without noticing much difference.
Generally, anything between 120 –140 Fahrenheit is great. Avoid going beyond or below this range to avoid attracting bacteria into the water heater.
Insulate the Pipes
To prevent possible fire outbreaks, consider insulating the pipes connected to the heater. This includes both cold and hot water pipes.
Opt for Modern Appliances
If you have any appliances in your home, such as a washing machine or dishwasher that you’ve been using for over 10 years, consider replacing with a new one. Newer versions of these appliances are usually more efficient and don’t use as much water as the older models.
Use Cold Water for Basic Tasks
One of the best ways to cut down your hot water use is to use cold water for basic tasks such as laundry, cleaning dishing, and brushing your teeth.
Repair Leaks Once Detected
Once you detect leaky faucets or pipes, have them repaired immediately to avoid wasting your hot water.
Perform Annual Checks
It’s a good idea to have a professional carry out checks on the water heater at least once a year. This will help you to discover leaks, rust, or other possible issues in the system just before they escalate.
Replace an Old Heater
Once a tankless heater is up to 15 years, it can get pretty rusty and less efficient. It becomes difficult to repair when it has issues. We advise replacing the unit at this point.
For storage heaters, 10 years is recommended for replacement.
Frequently Asked Questions
- What is the best on demand hot water heater?
For the best on demand hot water heater, the Rinnai RUC98iN is our top choice for natural gas, while the Tempra 24 Plus is our top pick for the best electric model.
- What is the best hot water heater on the market?
Here, our top choice is the Rheem RTGH-95DVLN for those who want something less expensive than Rinnai. We consider this to be the best gas-powered unit available. But don’t just take our word for it. Find out for yourself.
But again, you can’t go wrong with any of the other gas models on the list.
- Why are water heaters so expensive?
There are several factors that determine the cost of a product. In the case of water heaters, the type of technology and materials used are some of the deciding factors. For instance, most of them have copper and stainless steel, which are relatively expensive.
Also, the system is designed to last for a very long time, which is why they mainly use high-grade components. All these come at a price.
The tax return credits and utility rebate you get from such a product also makes their price higher.
- How healthy are water heaters?
Water heaters are healthy as long as you use them within their set temperature. Setting the thermostat too high or too low can attract bacteria or increase the risk of immune diseases.
- How long are water heaters good for?
The average lifespan of a tankless water heater is usually around 15 – 25 years. However, with proper maintenance, the unit can last longer.
- Is Rheem a good water heater?
Rheem is one of the leading brands in the world of tankless water heaters. And yes, they have some of the best quality products in the market.
A tankless water heater may seem like a costly investment initially, but the return, in the long run, is definitely worth more as long as you install the right unit.
Hopefully, choosing the right unit is a lot easier with our review of the best on demand water heater in the market.
We hope you found the article really helpful. Let us know if you have any more questions about finding the right model.