Rheem RTEX-27 Tankless Water Heater Review

Imagine never running out of hot water again. With the Rheem RTEX-27 240V 3 Heating Chambers Residential Tankless Water Heater, you can enjoy endless hot showers, reliable hot water supply, and an energy-efficient solution for your home. Featuring an external digital thermostatic control with LED display, this water heater offers precise temperature control. Its advanced self-modulation technology adjusts the power to meet your hot water demand, ensuring you never have to compromise on comfort. With durable copper immersion three heating elements and simple installation, this tankless water heater is designed for long-lasting performance. Say goodbye to cold showers and hello to a limitless supply of hot water with the Rheem RTEX-27.

Discover more about the Rheem RTEX-27 240V 3 Heating Chambers Residential Tankless Water Heater.

Why Consider This Product?

If you’re in the market for a tankless water heater, the Rheem RTEX-27 240V 3 Heating Chambers Residential Tankless Water Heater is definitely worth considering. This powerful and efficient unit offers a multitude of benefits that make it a top contender in its category. With its advanced technology, durable construction, and ease of installation, this water heater is sure to meet all your hot water needs.

Scientific research and evidence support the effectiveness of this tankless water heater. Its self-modulation feature allows it to adjust its power output according to your hot water demand, ensuring that you always have the perfect temperature water at your disposal. Moreover, the external digital thermostatic control with LED display offers precise temperature adjustments with an accuracy of +/- 1 degree. This level of control ensures that you can enjoy hot water at your desired temperature consistently.

The Rheem RTEX-27 240V also comes with certifications and endorsements that enhance its credibility. With its Energy Star certification, you can be confident that this water heater meets strict efficiency standards, helping you save on energy costs. Additionally, the positive customer testimonials attest to the product’s reliability and performance, further bolstering its reputation.

Features and Benefits

External Digital Thermostatic Control with LED Display

The external digital thermostatic control with LED display is one of the standout features of the Rheem RTEX-27 240V. This control panel allows you to easily adjust the water temperature to your desired setting. The LED display provides clear visibility, ensuring that you can precisely set the temperature with an accuracy of +/- 1 degree. Say goodbye to temperature fluctuations and hello to consistent hot water.

Most Advanced Self-Modulation

With its advanced self-modulation feature, the Rheem RTEX-27 240V adapts its power output to meet your hot water demand. This means that the unit will only use the necessary energy, saving you money on your utility bills. Furthermore, it ensures that you always have a steady supply of hot water, regardless of the demand. This feature is perfect for households with varying hot water needs throughout the day.

Durable Copper Immersion Three Heating Elements

The three heating chambers of the Rheem RTEX-27 240V are constructed with durable copper immersion heating elements. These elements provide efficient and consistent heat transfer, ensuring that your water heats up quickly and stays hot for as long as you need it. The field serviceable design allows for easy maintenance and replacement, making this water heater a cost-effective choice in the long run.

Simple Installation and Digital Temperature Display

Installing the Rheem RTEX-27 240V is a breeze, thanks to its simple design and 3/4 inch NPT water connections. The threaded connections make replacement quick and easy, and the digital temperature display adds convenience and accuracy. You won’t have to worry about complex installations or struggling to read the temperature settings with this user-friendly tankless water heater.

Product Quality

When it comes to product quality, the Rheem RTEX-27 240V excels in every aspect. Made with the utmost attention to detail and using durable materials, this water heater is designed to last. The copper immersion heating elements ensure efficient heating and long-lasting performance. With the ability to field service the heating elements, any maintenance or replacements can be carried out easily, ensuring that your water heater stays in top condition for years to come.

Rheem, the manufacturer of the RTEX-27 240V, is a renowned and trusted brand in the industry. Their commitment to providing high-quality products is evident in the reliability and efficiency of their water heaters. With this tankless water heater, you can have peace of mind knowing that you are investing in a reliable and durable product that will provide you with hot water whenever you need it.

What It’s Used For

Endless Hot Water for Your Shower

With the Rheem RTEX-27 240V tankless water heater, you can say goodbye to cold showers forever. This unit provides a continuous supply of hot water, ensuring that you can enjoy a refreshing and relaxing shower without any interruptions or temperature fluctuations. Whether you prefer a long, hot shower or multiple showers in a row, this water heater has you covered.

Ideal for Large Families

Large families often face the challenge of multiple people needing hot water simultaneously. The Rheem RTEX-27 240V is the perfect solution for such households. Its ability to modulate its power output according to the hot water demand means that every family member can enjoy hot water without any compromises. No more waiting for the tank to refill or running out of hot water during peak usage times – this water heater meets the needs of even the busiest households.

Energy-Efficient Solution

In addition to providing a constant supply of hot water, the Rheem RTEX-27 240V is also an energy-efficient choice. With its self-modulation feature, the unit adjusts its power output based on your hot water demand, resulting in significant energy savings. The Energy Star certification further validates its efficiency, making this water heater a sustainable and cost-effective option for your home.

Compact Design for Space-Saving

If you have limited space in your home, the Rheem RTEX-27 240V is the perfect choice. Its compact design allows for easy installation in tight spaces, freeing up valuable square footage. Whether you want to install the water heater in a closet, basement, or utility room, its small footprint ensures that it won’t take up much space.

Product Specifications

Power SourceElectric
Voltage240 volts
Heating Chambers3
Thermostatic Control Accuracy+/- 1 degree
Water ConnectionsBottom 3/4 inch NPT
Digital Temperature DisplayYes
Energy Efficiency CertificationEnergy Star
Maximum Flow Rate4.4 gallons per minute
Dimensions (H x W x D)13.9″ x 8.8″ x 3.6″
Weight12 pounds
WarrantyParts – 1 year, Heating Chambers – 5 years, Labor – 1 year

Who Needs This

The Rheem RTEX-27 240V tankless water heater is perfect for anyone looking to upgrade from a traditional water heater and enjoy the benefits of endless hot water. It is especially well-suited for large families with multiple hot water demands, as well as for individuals who value energy efficiency and space-saving solutions.

Pros and Cons


  • Precise temperature control with LED display
  • Self-modulation for optimal energy efficiency
  • Durable copper immersion heating elements
  • Easy installation and replacement
  • Energy Star certified for efficiency
  • Compact design for space-saving


  • Requires professional installation
  • Not suitable for extremely cold climates


  1. Is professional installation necessary?

    • Yes, professional installation is recommended to ensure proper setup and functionality.
  2. How much energy does the RTEX-27 240V consume?

    • The energy consumption depends on the hot water demand, but its self-modulation feature helps optimize energy usage.
  3. Does this water heater provide instant hot water?

    • Yes, the Rheem RTEX-27 240V offers instant hot water, eliminating the need for a storage tank.

What Customers Are Saying

Customers who have purchased and used the Rheem RTEX-27 240V are highly satisfied with its performance. They praise its ability to provide consistent hot water, its user-friendly interface, and the energy savings it offers. Many customers also appreciate the compact design, which allows for easy installation in spaces where traditional water heaters would not fit. Overall, the positive feedback from customers further highlights the value and reliability of this tankless water heater.

Overall Value

Considering its advanced features, reliable performance, and energy efficiency, the Rheem RTEX-27 240V tankless water heater offers excellent overall value. Its ability to provide endless hot water, coupled with the cost savings from reduced energy consumption, make it a worthwhile investment for any homeowner. With its durable construction and trusted brand reputation, this water heater is built to last, further enhancing its value.

Find your new Rheem RTEX-27 240V 3 Heating Chambers Residential Tankless Water Heater on this page.

Tips and Tricks For Best Results

To optimize the performance of the Rheem RTEX-27 240V, here are some tips and tricks:

  1. Set the temperature to your desired setting using the external digital thermostatic control.
  2. Regularly clean the heating elements to maintain their efficiency.
  3. Schedule professional maintenance to ensure the water heater operates at its best.
  4. Check the water connections periodically for any leaks or issues.
  5. Consider installing multiple units if your hot water demand is exceptionally high.

Final Thoughts

Product Summary

The Rheem RTEX-27 240V 3 Heating Chambers Residential Tankless Water Heater is a reliable and efficient solution for your hot water needs. With its numerous features, such as precise temperature control, energy-saving self-modulation, and durable copper immersion heating elements, this water heater offers superior performance. Its compact design, easy installation, and positive customer testimonials further enhance its value.

Final Recommendation

If you’re ready to upgrade your water heating system to a more efficient and reliable solution, the Rheem RTEX-27 240V is an excellent choice. With its ability to provide endless hot water, energy-efficient operation, and durable construction, this tankless water heater offers a compelling package. Whether you have a large family or simply desire a consistent supply of hot water, the Rheem RTEX-27 240V will meet your needs and exceed your expectations.

Discover more about the Rheem RTEX-27 240V 3 Heating Chambers Residential Tankless Water Heater.

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