Tankless Water Heater Reviews

best tankless water heaterWinter is not a wonderful time for everyone. Traditional house owners have no other choices than spending ton of money for heating setting. This is why tankless water heater brings people to new era. The overall size of this machine is smaller than previous model. You don’t have to spend big space to store it.

There is one problem, though. It is quite difficult to find suitable products based on tankless water heater reviews. Why? Some other products have maximum three to five good item recommendations. With tankless heater, you will see more than seven top quality items. Walking into nearby store without any preparation will make you confused.

In order to prevent such event, you should find detailed information about each item. Consider important factors of great qualities based on your need. It might be a little bit complicated in the beginning, but you will appreciate the process in the end.

How We Choose Products for Our Tankless Water Heater Reviews

There are several steps that we can go through to choose the right products:

Consultation With Plumbers And Professionals

Why plumbers are best source of information? It is because they work directly with the machine and knows how well this machine is. Are they just any plumbers and professionals? Not really. Correspondents of this consultation are support staffs, installers, and many more. Note that only HVAC workers belong to professional’s category.

Some people might not believe this fact that plumbers have tendencies towards certain brand. Common people usually think that plumbers only work based on customers’ request. In fact, plumbers often recommend popular brands. Several brands have top value; one has great durability, another has average power, etc. Once again, it all goes back to customers’ decisions.

How to collect samples from these professionals? It is easy. Listen to which brands they mention the most. If your house has specific conditions, don’t hesitate to ask whether similar product will still work the same. Plumbers are first hand handlers, so they might get something from their previous experiences. Don’t forget to match it with product review written online.

Brands With Great Reputations

As mentioned previously, there are lots of tankless heater brand. From one country only, you could se more than three brands. Try to calculate how many brands available from all over the world! Instead of seeing this condition as disadvantage, you should be happy for the options. Remember that each state or city is affected by different winter effect.

Thus, collecting as many options as possible will help you determine which heater is most suitable for your house. Also, every heater usually offers different system, efficiency, size and price. Moreover, you should look at its fuel type. Do you have easy access to this fuel? If not, then switch to another option immediately.

One more thing; you must aim to get best value product. Criteria for highest value will be great features with affordable price. Even when you need to pay more, make sure you get powerful engine or the other top notch features. Don’t forget to calculate heater’s maintenance costs and energy consumption. It is better to pay a little bit more than paying pricey bills annually.

Special Features

Your journey to collect date of tankless heater will be long and challenging. Tons of options will immediately pop on first page of your search engine. Here is a little tip; list some similar features from most tankless heaters first. This way, you will be able to consider which brand offer standard features but with higher price. Then, you should also note heaters’ special features.

Usually, special features are highlighted or underlined by heaters’ manufacturers. You will have no difficulty to find them on its official website. Don’t be too excited about some terms you never heard before. There is no guarantee that it will upgrade tankless heaters’ functionality. You should pay attention to “how it works” instead.

If you are not technical person, then reading some reviews from trusted sites will help a lot. These links are good shortcut to know pros and cons of special features. Some articles often include whether they are worth to buy or not.

Condensing Technology

For your information, most common problem with heaters is overheated venting pipe. Water heater not only extracts heat, but also releases heat as residue. Without condensing technology, heat residue will reach more than 100 degree Farenheit. Not all materials could handle this level of heat repeatedly. There might be no problem in the beginning, but soon you will need to replace the pipe.

Condensing technology recycles heat. Before heat residue reach venting pipe, it will be re-distributed to water. Thus, you will save more energy. Tankless heater without condensing technology consumes more energy as they rely on one energy source only. Since condensing technology could use heat residue to reheat water, heater machine will absorb less energy.

In addition, choosing tankless heater with condensing technology will allow you to choose less expensive venting pipe material and spend minimum cost on installation service. You should only aim for material that could handle 100 degree Farenheit heat. There are a lot of available options in the market.

Customer Support and Warranties

For those who buy tankless heater for first time, there will be times when you need to call customer service. It might be about confirming error indications, claiming warranty, asking for nearby service center, and so on. A good company should have good customer service as well. Then how do you know if costumer service has top quality performance?

There are three simple requirements.

First, you as customer shouldn’t be calling repeatedly to speak to knowledgeable representatives. Maximum number of call would be twice. If you need to call them three times or more and speak to front office only, then this brand’s customer service is not good.

Second, you should be able to find user manual and FAQ sections on the website. Not all people will immediately grab their phone and give a call. Some customers prefer to find explanation on official sites first.

Third, excellent customer service must have deep level of support. Believe it or not, many customer services only answer your question without offering any further solution.

Diverse Flow Rates

How many people live in the house? The more people live inside a house, the bigger GPM you will need. Big GPM tankless heater makes sure that each bathroom has hot water even when they are turned on at the same time. For example, 10 GPM tankless heater will provides maximum 10 gallons per minute. What if your house needs more than 10 gallons?

There are two scenarios for this case. First, you will get warm water with lower flow rate. Second, heater machine might fail and cannot heat water properly. Among these two options, it is better to take first condition. No one likes to bath with freezing water during winter. Make sure your chosen tankless heater offer this technology.

Those whose family has four to five members should take smaller tankless heater size. Best options will be 4-6 GPM units. However, it is better to list daily water usage beforehand.

Best Tankless Water Heater Ratings

Navien NR Condensing 98

Navien NR Condensing 98With thermal efficiency of 0.98, this tankless water heater is said to be the most efficient model ever manufactured in the industry. The secret lies on the built-in condenser which is designed to “preheat” incoming water with the help of flue gases. Such a technology is capable of minimizing – if not stopping completely – the wasted cold water that precedes the hot one, which is normally found in many tankless installation. The warranty for this model is valid for 15 years and along with the tankless water heater, consumers are also given the accompanying buffer tank and recirculating pump which can help decrease the rate of cold water burst during shower.

Rinnai R75LSiN

Rinnai R75LSiNCapable of providing a flow rate of 7.5 GPM of hot water, this gas powered heater deserves all the attention. Besides, it has received Energy Star rating, meaning not only is it energy efficient but you can also claim the federal tax credit and state rebate which will cut down the installed cost drastically. Note that the tax credit and rebate are only valid if you install the heater on your existing primary house. You can’t apply for them if the installation is dedicated to your new or secondary resident. Another good thing to point out from this model is its impressive build quality and 12-year warranty. Sadly, this tankless water heater comes with neither buffer tank nor recirculating pump, so expect to see some burst of cold water when you have a shower.

The Most Common FAQs About Tankless Water Heaters

How Do They Work?

Tankless heater only produces hot water when you want to. This heater is connected to tap water. After you turned faucet, water will flow into heater. There is a small water flow sensor that will detect how strong the water flow is. This information will be sent to heater’s computer. A burner will be ignited.

Then, water will be forced to go through heat exchanger. During this process, cold water will be set to certain temperature. Not long after, hot water flows out. Turning off the tankless heater will shut the entire operation.

How Much Do They Cost?

There is no definite answer for this question. You literally have to pick which heater you want first. Each tankless heater has different price tag and quality. It is affected by size and features as well. If you are buying for small houses or summer houses, affordable items are available. Bigger houses might need more expensive unit with more powerful heating component.

Don’t forget to consider installation cost as well. Tankless heaters from different brand have different level of installation complexity. Note that installing additional exhaust will be counted as additional cost.

Can I Install It Myself?

Since installation cost is quite high, you might want to install the unit by yourself. This could be an option to save money. However, you will lose your warranty. Unless you are professional HVAC plumber, there are possibilities to make errors. Company will not give you any warranty without proof of professional contractor installation.

There are several basic safety standards that should be followed, particularly for water line, gas size, and ventilation. When one factor is messed up, the others will not function properly.

How Long Do They Last?

Approximately, tankless heater could last up to 20 years or more. With proper installation and adequate quality of water, any heater will have no problem for 15 years at the maximum. If you love your heater, install it properly and have top quality water, then it will last for 20 years.

Those who wish longest life of tankless heater should do regular cleaning and maintain it professionally. By doing these steps, you are extending heaters’ durability. Letting it works without any maintenance would cut its durability.

How Much Can I Really Save?

In percentage, customers could save 25 to 50 percent on energy bills. This number is calculated based on comparison between tank heater and modern tankless model. When you calculate this money saving, don’t forget to consider lots of important factors.

Above all, you should look at its fuel; is it gas or electricity? Every energy source has different price tag. Simple calculation would call for less total amount after using energy efficient tankless heater. Since operating heater takes less energy, then overall bill should be reduced too.

How Do I Know The GPM Rate I Need?

If you want to know the answer to this question, then calculate the maximum hot water usage for your house first. At least, you could help by listing any activities that use hot water. Then, ask professional contractors to calculate GPM for you. After that, you have to compare several products that offer GPM capacity you need.

Tankless Water Heaters Buying Guide

The decision to switch or buy a unit of tankless heater should have strong reasons. For example, you want to have it to save money on energy bills. Then, you must find one product with best efficiency. Next, you might want product with reasonable warranty. Longer warranty represents the period of maximum performance guaranteed by company.

Another important guide to buy a tankless heater is choosing perfect GPM for your need. Consult with contractors for this point. Last but not least, think about what type of fuel you will use and whether you need to install additional venting system.

Factors to Consider When Buying a Tankless Water Heater

Is Purchasing A Tankless Water Heater Worthwhile?

Never buy something just because it is a trend. This rule also applies to tankless heater. You might hear that tankless heaters could save more energy than traditional tank heater. Do you know that the initial costs are higher than old tank heater? It takes three to four years before you could really save up money.

If you think this is a good deal, then you should start saving before stepping into nearby store. One unit of tankless heater’s price is three times higher than tank heater. Installation cost is not included yet.

Longer Service Life

Before buying a product, customers often consider the warranty. When you compare tank heater and tankless heater warranty, there are several years gap. Usually, tankless heater’s company offers 15 to 25 years of warranty. In the other hand, tank heater offers only six or ten years warranty at the maximum.

Check with company whether this warranty applies for the whole unit or certain part only. Read carefully the requirements to claim this warranty. In most cases, your tankless heater should be installed by professionals. If it is not, then your warranty is not valid.

Compact Design

How much space you need for tank heater? In addition to big space, you will also need complicated pipe circulations to deliver hot water. Compare all these hassles with perfect simplicity in a compact design from tankless heater. It comes in relatively small dimensions. You could put it near tap water without any additional setting.

Replacing tankless heater to different place is also possible. Again, you don’t need to build something to support tankless heater. Install them on the wall or outside the house to save more spaces.


You might wonder why many people buy tankless water and give up on their old heater. One main reason is its environmentally friendly feature. Unlike other products that might release harmful gas or residue, tankless heater minimizes any residue. It even incorporates a system to recycle its own heat residue. This makes tankless heater’s efficiency is quite high.

Those who want highest eco friendly tankless heater are purchasing electric unit. There is zero green houses produced. Isn’t that a great offer?


Customers who previously have tank heater then switch to tankless one will notice one thing. There are more parts in tankless heater. Instead of being a disadvantage, having a lot of parts allow contractors to fix or replace broken part only.

With old tank heater, there is higher chance to replace the whole unit than replacing one part. Why is it so? Water often leaks when contractors fix the broken parts. Thus, parts that work normally will be affected too.

Low On Operating Costs

Buying one unit of tankless heater and installing it is not the end of story. You will use certain energy to operate the machine. This is called operating costs. Theoretically, product with highest energy efficiency will have the least operating costs. In fact, energy bill is also determined by cost to provide energy as well.

Take a comparison of gas and electricity heater. Electric tankless heater has higher efficiency. Since gas is far more affordable, the operating cost of gas tankless water is lower.

Unlimited Supply Of Hot Fresh Water

Back in the old days, people used to calculate their shower time. The longer time they spend in bathroom, the more expensive energy bill you have to pay. In order to save money, you need to limit bathing time and amount of water used.

Say goodbye to those habits. After installing tankless heat, you will literally have unlimited hot water for your house. Simply turn the faucet and you will get hot water flow in no time.

What Type Do You Need?

In general, there are two options of tankless heater. They use different fuel to start their engine. Each has its own advantages and disadvantages.

1. Gas-Fuelled

Price wise, gas fuelled heater has higher price than electricity heater. It also requires professional tune up regularly. Despite of all those detailed services, gas heater has greatest performance and actually less operational costs. This product is highly recommended for any area with easy access to natural gas or propane.

If you wish to have instant hot water every time you turned on the machine, then consider to take unit with large burners. You could also install more burners to speed up heating process. Normal gas heater delivers 200.000 BTU per hour; almost three times hotter than tank heater.

Another item you should consider of gas heater is its venting type. There will be no problem if you put heater outdoor. When you bring it indoor, make sure to consult contractor for best venting option.

2. Electric

Initial cost to buy electric heater is less than gas one. However, you might need to upgrade electric capacity of your house. In order to start electric heater machine, you need large amount of energy. In terms or maintenance and repairing, this unit is easier to diagnose. Its simple design and compact size help contractors to fix any problem immediately.

Electricity is energy source with stable supply. It is not hard to get access to electricity. Therefore, it gives steady energy billing. You just need to upgrade electricity power beforehand.

What Size Do I Need?

In order to answer this question, you need to understand how manufacturers determine GPM rate. They are finding specific flow rate for certain water temperature. For instance, 4 GPM tankless heater will provide you with four gallons of hot water at maximum per minute.

If your personal calculation calls for higher flow rate, then you need to find tankless heater with higher GPM. Just for your information, gas tankless heater usually offers higher GPM than electric heater. You should definitely refer to this model first.

Number of Usable Bathrooms in a House

One factor that might determine which tankless heater to take is number of bathroom in the house. Without doubt, bigger houses require more powerful heater. There is a thumb up rule for sizing tankless size for you. One house with one shared bathroom for one to two persons requires 140.000 BTUs.

If the house has two bathrooms for three people, then find a tankless heater with 190.000 BTU capacities. For any house with three bathrooms shared with three to five persons, you need 380.000 BTU heaters.

Will You Use the Heater to Multitask?

You already know that you need to list how many people and rooms that need hot water. It is also important to check whether you are going to run hot water at the same time. Many houses need hot water for many purposes; taking a shower, cooking, or even doing laundry, especially in the morning.

In this case, you need to take large unit. Installing small unit will have a lot of risk. Water temperature might fluctuate quickly as it has low GPM.

Where Do You Live?

Tankless heater could be installed either indoor or outdoor. This installation preference should not be decided carelessly. You must check the temperature in your region first. Some areas have extreme temperatures that change within several hours only. In this case, you should install tankless heater inside the house.

Conversely, you could install heater outside if your area has stable temperature. Freezing heater unit would be hard to fix. It is better to prepare well beforehand.

How Many Do I Need?

For small houses, installing one tankless heater might be enough. However, there are several cases where one house takes more than one heater. What are those conditions?

First, house owners want hot water for multiple purposes at the same time. It has been mentioned previously that one heater will lower water overall temperature.

Second possible case is when a house has several bathrooms located in different corners. Installing pipes to different directions could be higher than installing a new unit.


Any electronic products have warranty from their manufacturers. In addition to years of warranty, you should also check whether this warranty is manufacturer to manufacturer or model to model. They will determine where you should go to claim warranty and what parts are eligible for repairing.

Also pay attention to documents you need to bring to claim warranty. Some good companies suggest their customers to register their products. This way, they could personally confirm that customers own certain products.

Energy Savings/Efficiency

Both gas fuelled and electric powered heater offer certain level of energy efficiency. Staffs will purposely highlight this information to attract customers. For electric heaters, this information is true as it is. Many stores claim that electric unit has highest efficiency and gas heaters rate for efficiency is lower.

Customers should ask further and learn about ignition option. Different ignition in gas heater could raise or decrease efficiency level. Among the choices, you should take direct ignition for best efficiency.


Durability of a water heating product is affected by several factors. They are quality of material, maintenance level and water quality. Material of each heater unit is represented from its price and brand. As long as you take top five recommended model, there is minimal chance to get false product.

Those who clean heater and maintain it regularly will have longer life expectancy. Similarly, customers who rarely check heater engine will have average or even less durability. Last, water quality is something you cannot change. Best effort you can do is straining any harmful mineral before turning the faucet.

Fuel Type

Tankless heater usually comes with two fuel options; gas and electricity. Before comparing their disadvantages and advantages, you must check the price for each energy source. If one is more expensive than another, simply pick the cheaper option.

Be careful when looking at electric heater. Installing one might require you to change your monthly electricity plan. If you are not ready with this change, it is better to take gas instead.

The Hot Water Flow Rate

Pay attention to flow rate. Bigger flow rate will be more suitable for a house with high demand of hot water. How to know whether the flow rate is big or small? The unit for flow rate is GPM. This one is important information any seller will put upfront. Once again, small unit only fits for small house with maximum three persons.


Remember that total price of tankless heater should include three details; heater unit price, installation costs and improvement costs. Heater units are sold for different prices. You could pick cheap or high price item. Installation costs will be determined by contractors and highly depend on your house setting.

Last, improvement costs cover electricity plan upgrade, additional venting or other details. List them carefully before buying one.


Installing tankless water heater is easy, but the journey to pick one model is quite challenging. There are a lot of factors to consider. A unit of tankless heater has different features. Every brand introduces different kind of extra features to get customers. If you are not well prepared, you will immediately get overwhelmed by all available options.

For this reason, you should find best tankless water heater before clicking online store or plan to get one. The best product is not always the priciest in the lists. It should be one heater that fits to your house need, meet your hot water demand and offer friendly operating cost. Otherwise, you might regret what you bought later.
Contact nearby contractors to consult installation cost. This information will help you decide whether to take tankless water heater or not. In the end, you could directly buy and install your dream heater. It is also possible to push back the plan so you could save more money.