Understanding High-Efficiency Tankless Water Heaters

Are you tired of running out of hot water just when you need it most? 

High-efficiency tankless water heaters might be the perfect solution for your home. 

Unlike traditional water heaters that store a limited supply of hot water, tankless models heat water on demand, ensuring you have a continuous supply whenever you need it. 

This innovative technology not only provides convenience but also offers significant energy savings.

Tankless water heaters, also known as on-demand water heaters, work by heating water directly as it flows through the unit. 

When you turn on a hot water tap, cold water travels through a pipe into the unit. 

A gas burner or electric element heats the water, delivering a constant supply of hot water. 

This eliminates the standby heat losses associated with traditional tank-style water heaters, making tankless models more energy-efficient.

 

Overview of Tankless Water Heaters

Definition and Basic Functionality

Unlike traditional water heaters that store a finite amount of hot water, tankless models heat water directly as it flows through the system. 

This innovative approach means you’ll never run out of hot water, no matter how long your shower lasts.

According to the U.S. Department of Energy, tankless water heaters can be significantly more energy-efficient than conventional storage water heaters. 

For homes that use 41 gallons or less of hot water daily, tankless water heaters can be 24%–34% more energy-efficient than traditional storage tank water heaters. 

For homes that use a lot of hot water—around 86 gallons per day—they can be 8%–14% more energy-efficient. 

Additionally, by installing a tankless water heater at each hot water outlet, you can achieve even greater energy savings.

The key to the efficiency of tankless water heaters lies in their on-demand heating mechanism. 

Traditional tank heaters keep a large volume of water hot at all times, which can lead to significant energy losses as the water cools and needs to be reheated. 

In contrast, tankless water heaters only heat water as it is needed, which can result in substantial energy savings and lower utility bills over time.

 

Benefits of High-Efficiency Tankless Water Heaters

Energy Efficiency

Are you looking for ways to reduce your energy consumption and save on utility bills? 

High-efficiency tankless water heaters offer a significant improvement in energy efficiency compared to traditional tank-style water heaters. 

Because they only heat water when it’s needed, these units eliminate the energy losses associated with storing hot water in a tank.

According to the U.S. Department of Energy, tankless water heaters can be up to 34% more energy-efficient for households that use 41 gallons or less of hot water daily. 

For those using more hot water, the efficiency savings are still notable, ranging from 8% to 14%​. 

These savings translate into lower energy bills and a reduced environmental footprint.

 

Continuous Hot Water Supply

Imagine never running out of hot water, even during the busiest mornings when everyone in the household is getting ready at the same time. 

With a tankless water heater, you get an endless supply of hot water because the unit heats water on demand. 

This means you can enjoy long showers and run multiple appliances simultaneously without worrying about depleting the hot water supply.

 

Space Saving

One of the significant advantages of tankless water heaters is their compact size. 

Unlike bulky traditional water heaters that require substantial space, tankless models are small and can be installed in various locations, including closets, under sinks, or even mounted on walls. 

This space-saving feature is ideal for homes with limited space or for homeowners looking to utilize their space more efficiently.

 

Longevity and Durability

High-efficiency tankless water heaters are known for their longevity. 

While traditional tank water heaters typically last 10-15 years, tankless models can last up to 20 years or more with proper maintenance. 

This extended lifespan means you won’t need to replace your water heater as frequently, providing better value over time.

 

 

Types of High-Efficiency Tankless Water Heaters

Electric Tankless Water Heaters

Electric tankless water heaters are a popular choice for many homeowners due to their efficiency and ease of installation. 

These units use electric heating elements to heat water on demand, making them ideal for homes where natural gas or propane is not available. 

Examples of highly efficient electric tankless water heaters include the Stiebel Eltron Tempra Plus and the EcoSmart ECO 27.

The Stiebel Eltron Tempra Plus is renowned for its Advanced Flow Control technology, which ensures a consistent hot water supply by automatically adjusting the water flow to maintain the desired temperature. 

This model boasts a 0.99 Energy Factor (EF), making it one of the most energy-efficient electric water heaters on the market. 

It also features a digital control panel for precise temperature adjustments and operates quietly, making it suitable for installation in or near living spaces.

The EcoSmart ECO 27 is another top performer, offering a compact design and a high energy efficiency rating. 

It uses self-modulating technology to regulate the amount of energy required to heat the water, resulting in significant energy savings. 

This model is particularly well-suited for smaller homes or point-of-use applications, where its 0.3 GPM activation flow allows it to respond quickly to hot water demands.

 

Natural Gas Tankless Water Heaters

Natural gas tankless water heaters are favored for their ability to deliver large volumes of hot water quickly and efficiently. 

These units typically offer higher flow rates than their electric counterparts, making them suitable for larger households. Notable models include the Rinnai Sensei Super and the Rheem Prestige.

The Rinnai Sensei Super series is known for its high performance and energy efficiency, with models offering up to 11 GPM. 

These heaters are Energy Star certified and come with a 10-year warranty on the heat exchanger, highlighting their durability and reliability. 

The ability to choose between natural gas and propane versions provides flexibility depending on the home’s fuel availability.

The Rheem Prestige model is another excellent choice, featuring a built-in water and gas leak detection system for enhanced safety. 

It offers a maximum flow rate of 8.4 GPM, making it suitable for medium-sized families. The space-saving design and digital remote thermostat make it a user-friendly option that combines performance with convenience.

 

Propane Tankless Water Heaters

Propane tankless water heaters are similar to natural gas models but use propane as the fuel source. 

These heaters are often chosen for their portability and efficiency, especially in areas where natural gas is not available. 

An example is the Rinnai V Series HE, designed for outdoor installation to provide hot water for pools, spas, or outdoor kitchens.

The Rinnai V Series HE offers a flow rate of up to 5.6 GPM and features an enhanced scale detection system to protect against internal damage. 

This model’s outdoor installation capability eliminates the need for venting, making it a versatile and durable option for various applications​.

 

Key Features to Consider

Flow Rate (GPM)

One of the most critical factors when choosing a high-efficiency tankless water heater is the flow rate, measured in gallons per minute (GPM). 

The flow rate determines how much hot water the heater can deliver at a given time. 

For instance, a unit with a higher GPM can supply hot water to multiple fixtures simultaneously, making it suitable for larger households.

When selecting a tankless water heater, consider the number of fixtures you plan to use simultaneously. 

For a household with multiple bathrooms and appliances running concurrently, a model with a flow rate of at least 7-9 GPM is advisable. 

In contrast, smaller homes or point-of-use applications may only require a unit with a 3-5 GPM rating.

 

Temperature Control

Consistent water temperature is crucial for a comfortable and efficient hot water supply. 

Advanced models of tankless water heaters feature sophisticated temperature control mechanisms. 

For example, the Stiebel Eltron Tempra Plus uses Advanced Flow Control technology, which adjusts the water flow to maintain the set temperature even when demand fluctuates.

This feature is particularly important in homes where multiple fixtures are used simultaneously, as it prevents sudden temperature drops or spikes that can be both uncomfortable and potentially hazardous.

 

Installation Requirements

Before purchasing a tankless water heater, it’s essential to understand the installation requirements, which can vary significantly between models. 

Electric tankless water heaters, such as the EcoSmart ECO 27, typically require significant electrical infrastructure, including multiple circuit breakers and specific voltage and amperage levels.

On the other hand, natural gas models like the Rheem Prestige often need venting systems to safely expel exhaust gases. 

Proper installation is crucial for the efficient and safe operation of the unit, and it is generally recommended to hire a professional installer to handle the job.

 

Maintenance and Durability

High-efficiency tankless water heaters are designed for longevity, but they still require regular maintenance to ensure optimal performance. 

Regular descaling and flushing are necessary to prevent mineral buildup, especially in areas with hard water. 

The Rinnai Sensei Super series, for example, includes features that alert users when maintenance is needed, helping to prolong the unit’s lifespan and maintain efficiency.

High-quality models often come with extensive warranties, such as a 10-year warranty on the heat exchanger, providing peace of mind and protection for your investment.

 

Top High-Efficiency Tankless Water Heater Models

Rheem® IKONIC™ Super High-Efficiency Condensing Tankless Water Heater

The Rheem® IKONIC™ Super High-Efficiency Condensing Tankless Water Heater stands out due to its advanced technology and exceptional energy efficiency, making it an ideal choice for homeowners in Frisco, Plano, Rockwall, and Grapevine. 

This model features innovative condensing technology, which captures and reuses heat from the exhaust gases to preheat incoming cold water. 

This process significantly enhances energy efficiency, reducing both operating costs and environmental impact. 

The unit boasts a high Energy Factor (EF), qualifying it for various rebates and incentives aimed at promoting energy-efficient appliances.

 

Rinnai Sensei Super

The Rinnai Sensei Super series is renowned for its robust performance and reliability. 

It offers models that can deliver between 7 and 11 GPM, making it suitable for large households with high hot water demands. 

These heaters are Energy Star certified, highlighting their superior energy efficiency. 

Rinnai’s Advanced Flow Control technology ensures a constant water temperature, even when multiple fixtures are in use, which is particularly beneficial during high-demand periods.

 

Stiebel Eltron Tempra Plus

The Stiebel Eltron Tempra Plus is a highly regarded electric tankless water heater known for its precision and efficiency. 

This model features Advanced Flow Control technology, which automatically adjusts the water flow to maintain the set temperature, ensuring a consistent and comfortable hot water supply. 

With a 0.99 Energy Factor, it is one of the most efficient electric models available.

The Tempra Plus is designed for easy installation and operation, with a digital control panel that allows users to set their desired water temperature precisely. 

Its compact size and quiet operation make it an excellent choice for installation in or near living spaces. 

This model is particularly suitable for smaller homes or point-of-use applications where space and efficiency are paramount.

 

EcoSmart ECO 27

The EcoSmart ECO 27 is an affordable and efficient electric tankless water heater, ideal for homeowners looking to upgrade from a traditional tank-style heater. 

It features self-modulating technology, which adjusts the energy usage based on hot water demand, resulting in significant energy savings. 

The ECO 27’s compact design makes it easy to install in tight spaces, and its 0.3 GPM activation flow allows it to respond quickly to low-flow demands.

This model is well-suited for smaller homes or individual fixtures, such as a bathroom or kitchen sink. 

Its affordability, combined with energy efficiency, makes it a popular choice for budget-conscious homeowners seeking a reliable hot water solution.

 

Installation and Maintenance Tips

Choosing the Right Installer

Selecting a qualified installer is crucial for ensuring the efficient and safe operation of your high-efficiency tankless water heater. 

For residents of Frisco, Plano, Rockwall, and Grapevine, Benjamin Franklin Plumbing of Dallas, TX, offers professional installation services that are reliable and adhere to all local codes and standards. 

A professional installer can help you choose the right model based on your household’s hot water demands and existing infrastructure.

 

Regular Maintenance Practices

Maintaining your tankless water heater is essential to ensure its longevity and optimal performance. 

Regular maintenance tasks include descaling, flushing, and inspecting the unit for any signs of wear or damage. 

Here are some tips to keep your tankless water heater running smoothly:

1. Descaling: Mineral buildup can reduce the efficiency of your water heater. Descaling the unit at least once a year helps remove any limescale deposits, especially in areas with hard water. Some models, like the Rinnai Sensei Super, come with alerts to notify you when descaling is needed​.
2. Flushing: Flushing the system helps remove any sediment or debris that may have accumulated over time. This process involves running a cleaning solution through the unit to clear out any blockages.
3. Inspecting: Regularly inspect the water heater for any leaks, corrosion, or unusual noises. Check the venting system for obstructions if you have a gas-powered model, and ensure all connections are secure.
4. Professional Service: Schedule an annual check-up with a professional plumber to perform a comprehensive inspection and maintenance. This service will include checking the burner, heat exchanger, and other critical components to ensure everything is functioning correctly.

 

Conclusion

Switching to a high-efficiency tankless water heater offers numerous benefits, including improved energy efficiency, continuous hot water supply, space savings, and long-term cost savings. 

By choosing the right model and ensuring proper installation and maintenance, you can enjoy reliable hot water and lower energy bills for years to come.

 

Frequently Asked Questions 

1. What is a high-efficiency tankless water heater?

   A high-efficiency tankless water heater heats water on demand without using a storage tank, making it more energy-efficient than traditional tank heaters. These units provide a continuous supply of hot water and save space due to their compact design.

2. How does a high-efficiency tankless water heater save energy?

   These heaters save energy by heating water only when it’s needed, eliminating standby heat losses associated with traditional tank heaters. Models like the Rheem® IKONIC™ and Rinnai Sensei Super use advanced technology and have high Energy Factors (EF), maximizing energy efficiency.

3. Are tankless water heaters suitable for large households?

   Yes, tankless water heaters are suitable for large households if the model chosen has a high enough flow rate (GPM) to meet demand. For instance, the Rinnai Sensei Super series can deliver between 7 and 11 GPM, accommodating multiple simultaneous uses.

4. What maintenance is required for a high-efficiency tankless water heater?

   Regular maintenance for tankless water heaters includes descaling to remove mineral buildup and flushing to clear sediment. Inspecting for leaks and wear is also essential, and many models, like those from Rinnai and Rheem, have maintenance alerts.

5. How much does it cost to install a high-efficiency tankless water heater?

   The installation cost for a high-efficiency tankless water heater ranges from $1,000 to $3,000, including the unit and professional installation. This initial investment can be offset by long-term energy savings and potential rebates.