What is a Tankless Water Heater: The Ultimate Buying Guide.

A tankless water heater is a device that heats water as it flows through the unit without storing it in a tank. This means that hot water is available on demand and there is no need for a large storage tank to keep the water hot.

Tankless water heaters have become a popular alternative to traditional tank-style heaters because of their energy efficiency and space-saving design. Unlike tank-style heaters that continuously heat water even when it is not in use, tankless heaters only use energy when hot water is needed.

This can lead to significant cost savings on energy bills. Additionally, tankless heaters take up less space and can be mounted on walls, making them perfect for homes with limited space. They also have a longer lifespan than tank-style heaters, typically lasting up to 20 years. Whether you’re building a new home or looking to replace an old water heater, a tankless water heater may be the perfect choice for your household.

What is a Tankless Water Heater: The Ultimate Buying Guide.

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Benefits Of A Tankless Water Heater

Tankless water heaters are a relatively new technology that offer many benefits over traditional water heaters. They are also known as on-demand water heaters because they instantly heat water as it flows through the unit, instead of storing it in a tank.

In this section, we will discuss some of the top benefits of a tankless water heater.

Energy Efficiency And Cost Savings

One of the main benefits of a tankless water heater is that they are much more energy-efficient than traditional water heaters. Tankless units only heat water when it’s needed, unlike traditional units that use energy to keep water continually hot, even when it’s not being used.

Here are some more key points to consider:

  • Tankless units can be up to 34% more energy-efficient than traditional storage tank water heaters.
  • They can save you up to $100 per year on energy bills.
  • Tankless water heaters have a longer lifespan, which means you won’t have to replace them as often as traditional water heaters.

Unlimited Hot Water Supply

Another significant benefit of a tankless water heater is that they provide an unlimited supply of hot water. Traditional water heaters store a finite amount of hot water in a tank, so you could run out of hot water if you’re using too much at once.

With a tankless water heater, you’ll never have to worry about running out of hot water.

Here are some more key points to consider:

  • You can run multiple appliances and fixtures at the same time without any loss of hot water.
  • Tankless water heaters deliver hot water almost instantly, so you won’t have to wait for the water to heat up.
  • You can enjoy a relaxing hot shower for as long as you’d like without worrying about the hot water running out.

Longer Lifespan Than Traditional Water Heaters

Finally, tankless water heaters have a much longer lifespan than traditional water heaters. While a traditional water heater might only last 8-12 years, a tankless water heater can last up to 20 years or more. That’s because they have less wear and tear on their components.

Here are some more key points to consider:

  • Tankless water heaters have fewer parts than traditional water heaters, which means there are fewer things that can go wrong.
  • Because they last longer, you won’t have to replace them as often, which can save you money in the long run.
  • Tankless water heaters take up less space than traditional water heaters, which gives you more options for placement.

Factors To Consider When Buying A Tankless Water Heater

Tankless water heaters have grown in popularity over the years as they offer a more energy-efficient and cost-effective alternative to traditional tank-based systems. However, with so many models and brands on the market, choosing the right one for your home can be overwhelming.

In this section, we’ll go over what factors you should consider when buying a tankless water heater.

Size And Capacity Based On Household Needs

One of the essential things to consider when buying a tankless water heater is the size and capacity you need. Different households have varying hot water needs, so you must choose a water heater that can meet your demands adequately.

Here are some factors to keep in mind:

  • The number of individuals in your household
  • The size of your home
  • The number of bathrooms, showers, and other water appliances in your home
  • The peak hot water demand of your household, which is the maximum amount of hot water needed during busy times

Energy Source Availability And Cost

Tankless water heaters operate using either electricity, natural gas, or propane. So, it’s vital to know the availability and cost of each energy source in your area before choosing a water heater. Here are some things to keep in mind:

  • Electricity is readily available almost everywhere, but it may come at a higher cost.
  • Natural gas and propane may be cheaper than electricity, but they may not be available in your area.
  • Consider the cost of installation and maintenance for each type of system.

Flow Rate And Water Pressure

Tankless water heaters’ flow rate and water pressure are other crucial factors to consider when buying a water heater. Flow rate refers to how much water your unit can heat at a specific time, and water pressure refers to how fast the water flows through your taps.

Here are some things to keep in mind:

  • The flow rate of your water heater should match your home’s peak hot water demands.
  • Your water heater’s flow rate can affect your water pressure, so it’s vital to choose a unit that can handle both.
  • Low water pressure can cause damage to your water heaters, so ensure your home’s water pressure is adequate.

Efficiency Rating

Tankless water heaters are known for their energy efficiency, so it’s essential to consider their efficiency rating when purchasing one. Here are some things to keep in mind:

  • The efficiency rating of a water heater is typically expressed using the uniform energy factor (uef) rating.
  • Choose a water heater with a higher uef rating as it indicates it uses less energy to heat water.
  • High-end units may also have extra features such as modulating burners that can adjust hot water output based on demand and save energy.

Installation And Maintenance Requirements

Lastly, you must consider the installation and maintenance requirements of the tankless water heater you want to buy. These are some things to keep in mind:

  • Proper installation is crucial for the optimal performance of your unit, and it’s best to have it installed by a licensed professional.
  • Tankless water heaters may require periodic maintenance such as flushing of the heat exchanger to prevent mineral buildup, and it’s essential to factor this into your budget.
  • Some water heaters may come with extended warranties if installed by a licensed professional.

Electric Vs Gas Tankless Water Heaters

Tankless water heaters are an excellent choice if you’re looking for a more efficient option to heat your home’s water. With the two types available – electric and gas – it can be challenging to decide which one best suits your needs.

While both types have their advantages and disadvantages, the choice ultimately comes down to what’s best for your household. We will discuss the major differences, advantages, and disadvantages of each type, along with cost comparisons and payback periods.

Differences Between Electric And Gas Tankless Water Heaters

  • Fuel source – electric tankless heaters use electricity, while gas tankless heaters use natural gas or propane.
  • Flow rate – gas tankless heaters provide a higher flow rate compared to electric heaters.
  • Installation – gas tankless heaters require a venting system and should be installed near an outside wall. Electric tankless heaters do not require venting, and their compact size means they can be installed anywhere inside your home.
  • Maintenance – gas tankless heaters require regular maintenance, while electric tankless heaters have less upkeep.
  • Lifespan – gas tankless heaters have a longer lifespan than electric tankless heaters.

Advantages And Disadvantages Of Each Type

**electric tankless water heaters**


  • Energy efficient
  • No need for venting
  • Less maintenance required
  • Compact design for easy installation


  • Lower flow rate
  • Can only run one hot water application at a time
  • Electricity rates can be costly

**gas tankless water heaters**


  • Higher flow rate
  • Can run multiple hot water applications at once
  • Long lifespan


  • More expensive to install
  • Require regular maintenance
  • Require a venting system
  • Not as energy efficient

Cost Comparison And Payback Period

Electric tankless heaters are generally more affordable to purchase and install than gas tankless heaters. The cost of installation for an electric tankless heater is around $500-$700, while gas tankless heaters may cost around $1,000-$1,500.

While electric tankless heaters are more energy-efficient, they have a lower flow rate, which may not be sufficient for larger households. Gas tankless heaters are more expensive to purchase and install, but they have a higher flow rate, making them adequate for larger households.

The payback period for an electric tankless heater may be shorter than for a gas tankless heater because of the lower initial cost and higher energy efficiency. However, if you have a larger household, it may be worth investing in a higher flow rate gas tankless heater, which may have a higher payback period but will provide the required hot water demand.

Both electric and gas tankless water heaters have their pros and cons. Ultimately, the decision will depend on what is best for your specific needs and preferences and household size.

Tankless Water Heater Installation And Maintenance

Tankless water heaters have become increasingly popular in recent years. They are highly efficient and provide a continuous flow of hot water on demand. However, installing and maintaining a tankless water heater can be challenging, especially for those who are not familiar with plumbing and electrical work.

In this section, we will explore the key aspects of tankless water heater installation and maintenance.

Locations For Installation

When it comes to tankless water heater installation, location is essential. The ideal location for a tankless water heater is close to the point of use, such as the kitchen and bathroom. Here are some other considerations for tankless water heater installation:

  • Tankless water heaters can be installed both indoors and outdoors. If you install a tankless water heater outdoors, make sure it is protected from freezing temperatures.
  • The installation location should be easily accessible for future maintenance.
  • Make sure that the area is well-ventilated and that the hot air can escape.

Necessary Plumbing And Electrical Requirements

A tankless water heater requires both plumbing and electrical work for installation. Here are the essential plumbing and electrical requirements for installing a tankless water heater:

  • A tankless water heater requires a dedicated gas line or separate electric circuit.
  • A water softener may be required depending on the quality of the water in your area.
  • A pressure relief valve and shut-off valves are necessary for safety reasons.

Maintenance Best Practices

Maintenance is critical to ensure the longevity and efficiency of a tankless water heater. Here are some best practices for maintaining a tankless water heater:

  • Flush the tankless water heater once a year to remove any buildup, which can affect its efficiency.
  • Check the filters regularly and clean them if necessary.
  • Inspect the unit for any signs of leaks or corrosion.
  • If you notice any problems, such as a drop in water pressure or temperature, contact a professional plumber for inspection and repair.

Troubleshooting Common Issues

Even with regular maintenance, issues may still arise with your tankless water heater. Here are some of the most common problems and how to troubleshoot them:

  • No hot water: Check the unit’s power source, gas or electrical, and ensure that the valves are open.
  • Inconsistent water temperature: Check the water flow rate and make sure that it is within the recommended range.
  • Unit makes unusual noises: Check for any loose connections or mineral buildup.

Installing and maintaining a tankless water heater requires some knowledge of plumbing and electrical work. Following the proper installation procedures and regular maintenance practices will help ensure that your tankless water heater provides you with hot water on demand for years to come.

Frequently Asked Questions For What Is A Tankless Water Heater

How Does A Tankless Water Heater Work?

A tankless water heater heats water directly without the use of a storage tank. When a hot water tap is turned on, cold water travels through a pipe into the unit. Either a gas burner or an electric element heats the water to the desired temperature.

What Are The Advantages Of A Tankless Water Heater?

With a tankless water heater, you can save money on your energy bills because it only heats water when needed. It also takes up less space than a traditional water heater and provides an endless supply of hot water.

How Much Does A Tankless Water Heater Cost?

Tankless water heaters can be more expensive than traditional ones, with initial installation costs being higher. However, they can save you money in the long run because of increased energy efficiency. The cost will depend on the model, fuel type, and your home’s needs.

Are Tankless Water Heaters Difficult To Install?

Installation of a tankless water heater can be difficult and requires a professional plumber. Many homes may require retrofitting, and gas models will require proper venting. It’s best to contact a professional installer to ensure proper installation and safety.

Can A Tankless Water Heater Meet My Household’S Hot Water Needs?

A properly sized tankless water heater can meet your household’s hot water needs. It’s important to consider the demand for hot water in your home and choose a model that can handle the maximum expected demand. A professional installer can help you choose the right unit for your needs.


A tankless water heater is one of the most innovative and efficient ways to provide hot water on demand without having to store water in a tank. After having gone through this blog post, you now have a better understanding of what a tankless water heater is and how it works.

It is essential to consider several factors before deciding if a tankless water heater is the right option for your household. Factors such as the size of your home, the number of people in your family, and your hot water usage patterns are all critical considerations.

By keeping all these factors in mind, you can decide if a tankless water heater is the best option for your home and take advantage of all the benefits that such a unit can offer you. With this innovative technology, you can expect to save energy, space, and money while enjoying an endless supply of hot water whenever you need it.