Best Tankless Water Heater 2017 – Buyer’s Guideby Steve Jackson | Last Updated January 1, 2017
Tankless water heaters allow to get amount of hot water, that would be enough to take a shower. However, they have a significant disadvantage – they require electrical grid to have certain parameters. It is not only that electrical wiring of old residential houses usually can not handle equipment more powerful, that 3,5 kW, but also devices with a power consumption from 10 kW and more will definitely need a three-phase network. This is why you would have to waste some money for the modernization of your communications besides the purchase of a tankless water heater itself. If you are ready to do that, then keep on reading.
So, what models of tankless water heaters you should exactly choose for your house? In order to provide you with an easier answer to this question, we offer you the list of the top 10 of the most famous devices of such a type.
|Noritz NRC661-DV-NG||6.5||Natural Gas||No|
|Rinnai RL94eP (Editor’s Choice)||9.4||Propane||No|
|Navien NPE-240-A||5.5||Natural Gas||Yes|
|Rheem EcoSense 8.4||8.4||Natural Gas||No|
|American GT505PI||9.4||Propane (LP)||Yes|
|EZ Supreme||6.4||Propane (LPG)||Yes|
|Takagi TH3DV TH3||9.9||Natural Gas||Yes|
Table of contents
Noritz NRC661-DV-NG – Indoor Condensing Direct Tankless Hot Water Heater
This device heats water on demand, using natural gas, but it also requires electricity for ignition, providing its electronics with power and preventing the internal parts of it from freezing up. It has simple temperature controls, and separately you can purchase a useful remote control with a good-looking digital display. The water heater itself has a direct vent kit that uses PVC pipes, but nothing stops you from getting a non-direct vent conversion kit if you want to mount the unit a non-exterior wall.
During the active use, this Noritz tankless gas water heater needs at least 60 watts of electricity. Though, this number increases to almost 135 watts during the use of the anti frost mode.
Besides connecting this tankless water heater to an electric outlet, you have a very useful ability to rig it to an accumulator backup, so you’ll be able to protect yourself from power outages. It has an energy factor of 0.91 – it is a big number for a gas-powered device. It is 93% efficient, no matter how you use it – with natural gas or propane.
Inside the device you will find a couple of heat exchangers, that are made from commercial-grade copper. It is 1.25 times thicker than the common copper, which is used in other water heaters of such type. Noritz offers a twelve-year warranty with these devices. The heater is equipped with a whole bunch of different safety features, such as a fire sensor, overheating and lightning protection devices, protection from freeze, a fan rotation detector, a condensate overfill detector and a temperature control lock.
The fuel consumption can range from 15 to 115 thousand British thermal units per hour. This is suitable only for low water flow rate of 1/2 GPM.
Such low results mean that the heater can only be used to provide the maximum of two showers with hot water at once. During the winter it can be used to heat water to temperatures ranging up to 60 degrees Celsius. You can choose one of the three temperatures from the unit itself. The remote allows you to choose from nine temperature settings, but it is being sold separately.
The Rinnai RL94eP Propane Tankless Water Heater is one of the best propane tankless water heater on the market. The unit is very versatile – it suits for any purposes. It will be good for small homes and for big offices, and it is easy to install even for people without any experience.
The system uses propane to heat the water, so you will have to keep an eye on the flame, but it doesn’t require any more maintenance than an ordinary gas-powered stove.
Some of the specifications you need to know about before buying this thing:
• Flow rate. The Rinnai RL94eP delivers up to 35 liters per minute depending on where you live and the temperature outside the house. In moderate temperatures you will get the promised 35 liters/minute, in very cold climate you may receive lower results.
• Power. The device requires 199,000 BTUs.
• Size. The Rinnai RL94eP weights only 20 kilograms. This is a compact and light unit, that will be suitable even for the smallest houses.
• Maximal temperature. The maximal temperature this heater can provide is 85 degrees Celsius.
Since this is a propane heater, it uses a system of internal sensors and heat exchangers. The burner need a live flame. These features allow the Rinnai RL94eP to service multiple bathrooms at the same time. I really mean it. You can turn on every tap in your house on the maximal flow and the unit will not fail you. Do not be afraid to take showers while your wife is using dishwasher and washing machine at the same time.
Anyway, I recommend you to test it for yourself during the first day of use to be sure how hard you can push it.
The installation process is very simple. It only took me an hour to install The Rinnai RL94eP. It doesn’t matter, where do you mount it: on exterior or interior walls. The venting system will need to have access to the fresh air and you have to somehow protect if from getting wet. The heater includes a detailed installation guide, so there shouldn’t be any problems.
Rinnai RUC98iP – Ultra Series Propane Tankless Water Heater
The Rinnai RUC98iP is an average tankless water heater that can be used by a variety of users. It offers fast and efficient water heating that provides safe and continuous operation. This unit can easily offer up to 20 years of quality work. Manufacturer offers you 12 years of warranty on heat exchanger and 5 years on other parts.
I laid my eyes on this unit when my old water heater finally stopped working (I had it for more than ten years). It has a reasonable price and provides users with 9.8 gallons per minute of hot water.
The Rinnai RUC98iP turned out to have bigger sizes, than I expected. It has been installed for almost four months already and here is my observations. It works really fast! The kitchen sink, which is the furthest away from the heater, takes just a couple of seconds to heat. I think, that it is acceptable. The shower on the second floor needs to be turned for 10 seconds before it fully heats. When I use it I does not feel if someone else is using hot water. After my old heater it felt amazing to finally enjoy such a constant flow of warm water.
It comes with an installation manual, but I recommend you to hire a professional that will install it for you. I installed it myself – it wasn’t very easy and took me about ninety minutes to do it. Though of course you can save some money and do it yourself, especially if you are not new to water heaters. The manual is pretty detailed and easy to understand.
Noritz NRC98-DVLP – Indoor Direct Vent Propane Condensing Tankless Water Heater
The Noritz NRC98-DVLP is a pretty expensive propane condensing water heater, that does not use tank. The unit is durable end efficient. It is constructed by professionals on Japanese factories, so there is no doubt that you will get a well-made, long lasting device.
The Noritz offers 12 years of warranty for this water heater. It is a standard period for water heaters of this class, that will ensure you with the safe and quality work.
The unit has a nice cleat on the back of it – it can be used for convenient placement on the wall. It only weights 30 kilograms – this is not a huge number for a water heater, so do not be afraid to put it on the wall in order to save some space.
It can be installed by an average user. It took me about an hour to do it. At first I kept the default settings – 45 degrees Celsius, but it wasn’t enough, so I changed it to 55 degrees – and it felt just right.
It is very quiet. When I turned the device on I thought it was broken – but this is just the way it works. It is very silent when compared to any other tankless water heaters on the market. It is also pretty effective – it suits for a home with three bathrooms and provides almost immediate water heating, while consuming 16 thousands of British thermal units, peaking at 180 thousands btuh. These numbers are really impressive.
Navien NPE-240-A – Tankless Gas Water Heater
The Navien NPE-240-A is a high-efficiency gas water heater, which provides ecological and immediate water heating. It uses condensing technology that uses additional heat, that always gets lost by other water heaters.
The Navien NPE-240A’s energy factor is superior when compared to both traditional water heaters and noncondensing tankless models. It has reduced vent temperatures thanks to the mentioned condensing technology, which allows you to use PVC venting, that will save you a lot of money and provide with the ease of installation.
Among the most interesting features of this device I want to mention:
- The ComfortFlow technology – it is Navien’s famous super-effective recirculation system, which is included in the NPE-240-A. It connects a small insulated buffer tank with a recirculation pump, ensuring that with the help of the NPE-240A you will instantly receive hot water at any moment;
- NPE-240-A Eco uses a bunch of technologies, that will help to reduce your house’s impact on the environment. Ecological pre-mixed burners are decreasing CO and NOx emissions. It can be done by merging gas heating and air before ignition. This provides you with almost 75% reduction in polluting emissions. By choosing a Navien NPE-240A, you are reducing the same amount of CO2 as 31 cypress trees.
- Everlasting durability. The Navien NPE-240-A Tankless Gas Water Heater uses stainless steel parts, which prevents corrosion and increases the lifespan of the device.
Rheem EcoSense 8.4 GPM 157,000 BTU – Ultra Low Nox Natural Gas High Efficiency Indoor Tankless Water Heater
A friend of mine recently bought this water heater, so I know firsthand about all of its features and drawbacks. Overall, my friend claims that Rheem EcoSense is a nice and balanced water heater. Let’s find out, if this is true.
First of all, it has PVC venting. It will provide you with very simple installation process and it is easier to replace in case of leaks. Rheem EcoSense’s ability to heat water on demand saves lots of energy when compared to many standard water heaters. It has nice and informative electronic controls and sensors and includes a horizontal vent termination kit.
It provides literally endless hot water on demand. Even when both washing machine and dishwasher are running, you can take a hot shower with a constant temperature. My friend has two big baths, a dishwasher and a washing machine. He lives with his wife only, so he does not need to run all these things at simultaneously, but he decided to measure his maximum potential hot water usage in gallons per minute in order to pick the most suitable device that will let him use two showers and either washing machine or dishwasher at the same time. He needed 2.3 + 2.3 + 3 = roughly 8 gallons per minute, so this heater was perfect for him. It is fast, durable and can be bought for an affordable price. Definitely a nice choice.
American GT505PI – Indoor Tankless Water Heater
The American GT505PI Indoor tankless water heater will provide you with continuous hot water, while saving you a lot of money due to its effective usage of propane. It has very convenient design, which lets it to be mounted in a wall, and includes a nice digital controller, using which you can precisely set the water temperature you need. It also gives you diagnostic information about the condition of the unit.
The GT505PI produces up to 9.4 gallons per minute of hot water. The heater can use a maximum 190 thousand BTU per hour of Propane.
Manufacturer provides customers with 12-year limited warranty on heat exchanger and 5-year warranty on other parts of the water heater.
Like most of the modern gas heaters, the American GT505PI needs a 3/4” gas line. You will have to upgrade your gas line if you have a smaller one, if you want to enjoy all the benefits of this well-made equipment.
It was easily installed according to the included installation manual (it took me about an hour) and worked excellently right after I turned it on. Default settings allow you to set the temperature up to 50 degrees Celsius. There are instructions in the internet that you can use to change some of the internal jumpers and set the temperature up to 60 degrees Celsius, but watch out – I guess that you will automatically lose the warranty if you do that.
Rheem RTG-84XLP 8.4 GPM – Low NOx Outdoor Tankless Propane Water Heater
This unit provides a great solution to heat your water at home for those who are limited in money. With the Rheem RTG-84XLP you will never run out of hot water again. Its energy efficient and space saving design will save you a lot of money. It is very durable, so you will not have to worry about your water heater for another decade.
I have had it for over a year. I mounted in on the wall outside the bathroom. It is pretty noisy – so place some rubberized isolators under it. It does not cause any inconveniences until you decide to visit this bathroom. When I am taking the shower it sounds like a truck is driving after me. But I can bear that for its low price tag and the fast and continuous water flow, that lets me enjoy myself during the water procedures.
If you are going to buy it, keep in mind, that it requires modern 3/4-inch line for the gas. This is a pretty common requirement for most of the new water heaters, so it should not be a problem.
The Rheem RTG-84XLP is a nice outdoor propane water heater. It is easy to maintain and suits great for a house with two bathrooms. Considering its low price, I recommend it to everyone who does not have too much money but wants to have a reliable source of hot water throughout the whole year.
EZ Supreme Tankless Water Heater – 6.4 GPM – Propane LPG
The EZ Supreme Tankless water heater is a most powerful and well-made model from the American EZ Tankless company. This water heater was made in order to suit the needs of largest American houses. It is a reliable and efficient heater. Components used in it are designed to offer many years of reliable service for every customer. This unit is capable of supplying a continuous flow of hot water for houses with up to four bathrooms. It delivers monstrous 6.4 gallons of hot water per minute.
Soon after the installation of this heater you will notice savings in energy use. You will never run out of hot water again! EZ Supreme made everything they could in order to provide you with all the hot water you need.
The device has a nice white exterior and slim modern design, including a convenient digital control panel. This model will look OK mounted anywhere in your house and will not take up much space due to its compactness.
The heater uses so-called “direct vent” – an advanced induction process. It provides the device with a sealed dual-chamber forced air intake and exhaust pipe. This revolutionary design captures ambient heat, that is being radiated from the combustion process. It makes this water heater even more efficient!
Takagi TH3DV TH3 Series 199000 BTU – Indoor Water Heater
The Takagi TH3DV TH3 Series 199000 BTU Tankless Water Heater is a quality heater, that suits for both commercial and home usage. It can be successfully used in small restaurants, beauty salons, barber shops and so on.
The Takagi TH3DV TH3 Series provides hot water flow to domestic water systems (either directly or indirectly). It can be widely used in combination with storage tanks, hydronic heating systems, recirculation systems, radiant floor systems, and last, but not last – with domestic heating applications.
Some of the feature of this model:
- It has an ENERGY STAR® certificate;
- 15-year warranty for the heat exchanger and five-year warranty for parts in case of Residential use;
- 6-year warranty for the heat exchanger and five-year warranty for parts in case of Commercial use;
- Provides flow rate of up to 10 gallons per minute;
- Its primary heat exchanger uses professional copper alloy, that provides 25 times better heat transfer, than stainless steel does;
- Its secondary heat exchanger is very efficient too and it uses 316L stainless steel, which provides corrosion resistance;
- Has all needed certificates for commercial applications;
- Easy-Link function allows to connect up to four different units without a Multi-Unit Controller;
- Multi-Link function allows to connect up to 20 units with the help of a Multi-Unit Controller;
- Integrated controls and power cord as standard features;
- Provides venting with Schedule 40 PVC, CPVC, PP and Category III stainless steel;
- Includes many safety features, such as freeze, overheat, surge protection, and even troubleshooting diagnostic codes.
The efficiency of modern water heaters
Starting from the principle operation of units, it is possible to make a hasty conclusion that the tankless water heater consumes more resources at the expense of significant power the heating element. However, this is not true.
In practice, it turns out, that the both types of heaters consume almost equal amount of recourses. The difference is that the tankless ones do their job with an increased intensity, but for a short amounts of time, and tank water heaters provide smoother, but prolonged heating process.
Weight and dimensions
In this aspect tankless water heaters outperform other types. Such a device does not require a tank for intake and storage of water. Tankless water heater can be easily install in places, where the storage device simply would not fit. For instance, under the sink or in some kind of niche.
Practicality and the level of convenience of use
- Tankless water heater has to produce at least 8 kW of power. This number will provide you with hot water even during the winter.
- A less powerful device can only meet the needs of the kitchen washstand for dishwashing – and nothing else. This is why you need to pay careful attention to this criterion. Insufficient power may lead to the fact that during the winter water from a tap would be barely warm.
- The storage system is much more convenient in this respect. After some time, that is required for heating, the system will let you enjoy the comfortable temperature of water, that can be set manually. Tanks with capacity of more than 80 liters will provide with an opportunity to take a bath. At the same time, devices with smaller capacity offer more efficient water usage.
- Another advantage of this type is that water can be supplied to multiple water receivers, for example – for the shower and the kitchen water dispenser. Similar features provided only with expensive models of tankless water heaters. Adding flows would cause a temperature jump on average models.
Household electric water heater can be successfully replaced by basins and pots, which many Russians use for domestic and hygiene needs during the annual absence of the hot water in summer. Using the device (considering that you chose it correctly and properly use it) can minimize the unpleasant consequences of this outrage in a city apartment. As for the country life, which often do not provide such benefits of civilization, like a hot water – a water heater can obviously make it easier and more comfortable throughout the warm season. Electric water heater can easily solve the main problems of the summer drought, artificially created by public services (for the sake of our own good, of course): you will be able to properly take a shower or wash dishes, using warm or hot water for domestic and other purposes.
In such a water heater water goes through a powerful heat exchanger and immediately heats up. It does not require too much space and can offer endless amount of hot water, and you will not have to wait until it warms up. Another unquestionable advantage of a tankless water heater is that it does not require cleaning and maintenance.
The main element of the construction in tankless water heaters is the heating element. Depending on the type of a device, it can be made using various methods:
- Uninsulated spiral;
- Shell and tube type heat exchanger;
- Folded tubular heating element.
Types of household electric water heaters
A narrow tube is used as the heating capacity, which provides rapid heating of water during while it flows through a heat exchanger.
Boilers are divided into two types:
Flow boilers. They have a compact size. The presence of a folded tubular heating element makes them quite easy to use. The heating element is strong enough and has a long service life. Cold water heats up while it passes through the tubular element, and then it flows out. The operating principle of instantaneous water heater – heating to the desired temperature all the water passing through it.
Storage boilers. They have a special reservoir for water. They do not create a heavy load on the power grid, which allows you to use devices of that kind even in older buildings.
Tankless water heaters are compact devices, that are able to immediately heat water that passes though the built-in heating element to the temperature up to 60 degrees Celsius (they are not able to provide you with boiling water). High power of the tubular element (up to 36 kW) ensures quick heating process. However, in everyday life are commonly used water heaters with significantly lower power – from 3 to 8.5 kW.
Tankless water heaters with power from 3 to 6 kW can be plugged in an ordinary electric single phase 220-volts outlet (domestic mains should be designed for the appropriate loads in order if you are going to use this method). More powerful models seem logical to use in apartments with electric stoves and plug in a three-phase 380-volts outlet.
Tankless water heaters differ from each other by the capacity of hot water, which they can produce for a minute of work. Household tankless models with the power at the range of 3 to 6 kW produce from 2 to 6 liters of warm water per minute, heating it up for no more than half of a minute. Such volume of heated water is usually quite enough for important household and hygiene needs.
There are two ways of connection for electric tankless water heaters: non-pressure and pressure. Non-pressure water heaters need to be mounted near the water point – they are only used to maintain it. Pressure units have to be built into the water standpipe. They can be used to maintain multiple draw-off points. For apartment usage a pressure water heater would be more reasonable, and non-pressure one will suit better in a summer house or garage.
It is believed that the main drawback of the operation of all tankless water heaters is their ineffectiveness in the context of electricity consumption. You can the minimize additional costs of electricity bills when using a tankless water heater by being as thrifty as possible with warm water consumption: short-term usage of a tankless water heater is unlikely to increase the electricity bills very strongly, this possibility only exists in the case of frequent and extended use of such devices. If there is no desire or ability to save water, you should better use a storage water heater.
Storage electric water heater – is an insulated tank, usually covered with anticorrosive and often with antibacterial inner coating. Water in it heats up with folded tubular heating element to the desired temperature (the temperature rage is wider here, water can be heated up from 30-35 to 75-85 degrees Celsius, depending on the model of water heater). The temperature keeps consistent – water heater turns on, when it gets a little bit colder (usually only for 0.5 or 1, the built-in thermostat is used to monitor this process), and then turns off. Automatic start of the heating process, of course, also happens when the tank is being refilled with water after consumption, since its level decreases with time. Operation in this mode allows to use electricity more efficiently.
Domestic storage water heaters plug in to an ordinary 220 V outlet. Power of these devices ranges from 2 to 3 kW, what can be compared with the power of a modern electric kettle. At the same times, due to such power, performance is also differ – water heats with storage models much slower than with tankless ones. But modern water heater, if it is of a pressure type (and majority of devices on the market are pressure), is able to provide hot water for all water points in the apartment; the larger the tank, the more actions using the hot water can be performed simultaneously: wash dishes, taking a shower or bathing, etc…
In apartments water heaters are usually being installed in bathrooms, so you need to relate the volume of the device and its dimensions with free space in the bathroom. In order to save space, you can choose horizontal models (if it will help you to save place). Also, there are built-in storage water heaters, which can be mounted under the sink, but they are a small capacity. Basically these heaters require a vertical (sometimes right on the floor) installation on the wall.
There are also water heaters of inlet type, that are relevant for the buildings with the lack of water supply system, including, of course, summer houses. Most often it is a plastic or metal container with a water tap, which is located inside the heating element. The water is filled manually in the water heater, and the device is mounted on the wall above the sink (there are also models with a sink in the set).
Many modern water heaters of both types are equipped with a residual current device (RCD), providing additional security in the context of connection to electricity. RCD stops the water heater in case of a leakage on the body (dead parts) and the cable (live parts). The device compares the input current at him with shock emanating from him, and if the difference is due to leakage of 30 mA, RCD automatically opens the electric circuit. Thus, the RCD protects a person from electric shock while using the heater. It is better to purchase water heaters with RCD included, this applies to both tankless and storage models. If you already use a water heater without the RCD, it can be purchased and mounted separately, but you will have to hire a qualified electrician to do that.
Review of non-pressure tankless water heaters
In this part of the article we offer you a closer information about some models of tankless electric water heaters. We have to mention, that tankless non-pressure models are a good option for summer houses, garages and other premises, where you need to provide a single water point with hot water. For apartments, if you wish to do dishwashing in warm water and to comfortably take showers, you will need to install two of such water heaters. Please note the following main criterion, that should be considered before choosing a device.
Decide, what exactly do you need a tankless water heater for: only to wash dishes and other kitchen needs, or you would like to be able, for instance, to take a shower. Depending on this, in fact, you should choose the effectiveness and power of the device you need.
Correlate the power of tankless water heater with the power of your home electrical network. In homes with older wirings you often have to take additional steps to safely connect such devices.
Note that if you have to use the water-heater in cold weather, the temperature of the incoming cold water will be lower than during the summer, which means, that the heater wouldn’t be able to provide enough power to heat water to your preferred temperature (using the same pressure of water flow).
Be sure to purchase tankless water heater with a residual current device (RCD).
Remember, that non-pressure tankless water heater is designed to maintain only one water point.
When purchasing a device, be sure to check the packaging unit and evaluate the build quality.
Installation of tankless water heater
During the installation of tankless water heater, you need to decide, what method of operation it will use and what will be the source of power. The cheapest way to heat water – gas boiler. If there are highway next to the house, then where wouldn’t be any problems. But in the absence of gas you will have to find other ways to heat water and rooms.
It is possible to install the boiler that runs on liquid fuel, but this would require a separate room for the equipment. Another good solution of problem is purchasing of an electric water heater. They are the easiest to use, but a little more expensive.
Unstable work of public services, responsible for the supply and maintenance of municipal water systems, and the desire to have the source of hot water at the cottage or country house are the reasons to buy and install a water heater. Before you choose a water heater – tankless or storage, you need to carefully examine their comparative features and make an informed decision. In many ways, the choice depends on the technical characteristics of your room, but it is also important to take into account other parameters of units.
Electric heaters are the most widely used for private operation. This trend is due to the reasonable price and ease of installation of the unit.
The principle of heating the water in these machines is tankless or commutative (in storage types). The operation of a storage heater is to take in water and heat it up to the desired temperature, after which the water can be used in necessary amounts.
Installing water heater, make sure that the wall can support the weight of the unit, multiplied by two. You will only need a 220 V outlet in order to power the device on the sufficient level.
Tankless water heater is more “capricious” during the installation. There will be a need for additional wiring arrangement and the availability of the circuit breaker. Powerful units, calculated on 9kW or more need to be able to connect to the three phases. There is also a positive thing – small dimensions allow to mount this device even on non-bearing walls.
Maintenance and exploitation of water heaters
Storage systems offer regular preventive maintenance. Attention should be paid to cleaning the heating elements from appearing scale, which appears in different numbers, depending on the quality of tap water. It is also necessary to replace the magnesium anode.
Tankless water heater does not require any special attention. The correct connection and exploitation will not cause problems with the device for a long period of time.
Final Words – Conclusion
Before choosing a water heater, you need to take into account many different factors, and the everyday hot water consumption is one of them, as well as room configuration in which it will be located, the power supply capacity, the number of people living in the house and many others. Before making a purchase, you can consult with an experienced professional who will indicate the main features of different models of water heaters, as well as help you choose the most suitable one.
During the choose, you should to focus on such indicators:
- What type of water heater do you need: the storage or tankless;
- Capacity of the tank;
- Speed of heating the water;
- The load on the grid;
- The necessary water consumption.