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Home » Water Heaters » Rheem Tankless Water Heater Reviews

Rheem Tankless Water Heater Reviews

By: David Trinh
Last Updated:
Rheem logo

You will have noticed when browsing Rheem hot water heater reviews that the name Rheem is associated with high quality and good customer care.

Rheem ratings are high for all types of water and air appliances, and tankless water heaters are no exception. The brand offers a variety of top-quality models: gas and electric, indoor and outdoor.

Top 5 Rheem Tankless Water Heaters

Rheem RTGH-95XLN
  • 9.5 GPM
  • Gas, Whole House
  • 0.94 Energy Factor Rating
  • 8.4 GPM
  • Gas, Whole House
  • 0.82 Energy Factor Rating
  • 8.4 GPM
  • Gas, Whole House
  • 0.82 Energy Factor Rating
  • 4.4 GPM
  • Electric, Point of Use
  • 0.99 Energy Factor Rating
  • 3.2 GPM
  • Electric, Point of Use
  • 0.99 Energy Factor Rating

About Rheem

In 1925, two of the Rheem brothers, Donald and Richard (along with some help from a third brother, William) began a co-partnership with Pacific Galvanizing Company. Their work initially involved galvanizing steel drums. As the business grew, they began to produce their own steel drums and other metal products under the name Rheem Manufacturing Company.

rheem single logo

In 1930, Rheem Manufacturing Company bought the Republic Steel Package Company. This led the brothers to start producing their own boilers and tanks. A year later, they expanded to gas tank water heaters.

After a short break from commercial work in the 1940s (during which time the company was contributing to the war effort), Rheem began to fully embrace consumer products. At the same time, the brand started producing commercial boilers as well. This growth led the company to open more plants across the U.S. and abroad. By the end of the 1960s, it had plants in a total of 19 countries.

In the 1970s, Rheem split into two divisions: the Water Heater Division and the Air Conditioning Division for HVAC. Having an entire division dedicated to water heaters meant that the company was able to start producing some of the highest-quality, technologically-advanced models available.

Today, Rheem is the biggest manufacturer of tankless water heaters in all of North America.

Where Is Rheem Made?

Rheem is based in Atlanta, but the company currently has manufacturing plants for water heaters in Alabama, Mexico, Australia, and China.

Types of Rheem Water Heaters

Rheem produces five series of gas (both propane and natural gas) and electric tankless water heaters. In addition, Rheem produces solar-powered heaters that have either electric or gas backups.

Rheem Water Heater Reviews from Consumers Online

consumer reviews

Rheem water heater ratings show that the general consensus among consumers is this is a top brand. 

After doing the research and analyzing customer reviews on numerous sites like Amazon and other forums below are our findings on the overall questions related to Rheem products.

Are Rheem Water Heaters Good?

Although Rheem tankless water heater prices can be higher than those of other brands, the cost is worthwhile for the caliber you receive. There are excellent options, whatever your needs, including models that are Energy Star rated and heaters with long warranties. Whereas Rheem hot water tank reviews are mixed (ranging from just below average to high), Rheem tankless heaters often rank top of their group, no matter the criteria.

Rheem Electric Water Heater Installation

A common theme in Rheem electric water heater reviews is the ease of installation. If you are replacing a standard electric water heater, you’ll find it particularly simple and fast to install a Rheem heater. The likelihood is that you’ll be able to do it yourself in under an hour.

Rheem Gas Water Heater Installation

As with all gas water heaters, installation is slightly more complex for a Rheem gas heater than an electric heater. You will need a qualified plumber. However, Rheem gas water heater reviews show that these heaters are no more complex to install than those of any other brand.

Rheem Electric Water Heater Temperature Adjustment

high efficiency

Rheem electric heaters come with a temperature preset of 120 degrees Fahrenheit. Most people find this appropriate, but some consumers say that they prefer to change the temperature. As the reviews point out, this is easy to do. You can set the temperature as low as 90 degrees Fahrenheit and as high as 150 degrees Fahrenheit — although more than 120 degrees Fahrenheit is not recommendable, as it increases the risk of scalds.

Even the most basic models offer easy temperature control. There is no need to turn off and open your water heater to access the thermostat — you can set the temperature on an external digital thermostat control. It is possible to change the temperature to whatever you want in one-degree increments.

Rheem Tankless Water Heater Maintenance


Reviewers point out that Rheem water heaters can have a long lifespan. This is even true for outdoor models, as they are rust-free and insulated for protection from the elements.

To maximize their lifespan, prevent breakdowns, and limit repairs, Rheem water heaters do require some maintenance. This includes regular cleanings to remove limescale and periodic inspections (especially for gas heaters). You should also call a professional if you notice anything different about how your water heater is running.

Rheem Hot Water Heaters Warranty and Customer Service

The warranty for a Rheem water heater depends on the model:

warranty guarantee
  • Performance and Professional Classic. The most affordable water heaters are those in the Performance and Professional Classic series. Both gas and electric heaters in these series have warranties of 6 years.
  • Performance Plus. One of the benefits you receive for a slightly higher price is a longer warranty — of 9 years.
  • Performance Platinum and Professional Prestige. At 12 years, the top-range models (those in the Performance Platinum and Professional Prestige series) have the longest warranty of all.

If you have a problem with your water heater during the time it is covered by the warranty, you can reach out to customer service. The brand is well-known for providing good customer care. You can submit a web form and wait for a response or call customer service directly — Rheem has dedicated numbers for customer service (which covers warranties and parts), technical service, and sales and marketing.

If you need help fast or you want to find the answer to a specific question about your water heater, you can find a list of FAQs or use live chat. There are separate live chat options for general information and for error codes appearing on the display. Finally, there is another customer service phone number to provide you with technical support just for issues related to EcoNet®.

Rheem’s Top Tankless Models

A Rheem water heater price depends considerably on the series of the heater.

At the low end, you have the standard series Performance and Professional Classic. It is important to note that, although these contain the most basic water heaters from Rheem, the heaters still have an energy efficiency of 99.8 percent.

Classic RTE models as well as RTEX water heaters both fall into this category. New models have EcoNet® capability, which allows you to track the performance of your water heater from any mobile device.

Next, there is mid efficiency like Performance Plus, which has both indoor and outdoor models. These have a slightly higher energy factor than standard models, thanks to all-copper heat exchangers to minimize transfer loss.

Finally, there are the high-efficiency heaters. This category includes Performance Platinum and Professional Prestige. In addition to offering even greater efficiency (particularly the condensing models), these heaters have improved safety and intelligent electronic controls.

Performance Series

Rheem Performance Classic Series

Water heaters in the Performance series have an energy factor of between 0.54 and 0.81 for gas and between 0.91 and 0.93 for electric. Both gas and electric models have lower maintenance needs than heaters in the same price range from other brands. Plus, the gas heaters are quieter than normal, which makes them ideal for indoor use.

With a GPM of 3.17 and wattage of 13,000, the RTEX-13 is ideal for a studio apartment or for a small family that only needs hot water for a single bathroom at a time. You’ll only need to wait around 15 seconds to receive the hot water.

Professional Classic Series

Rheem Performance Classic Series

Other low-end water heaters from Rheem form part of the Professional Classic series. Although they are some of the least expensive, they have high-quality components, are enabled for EcoNet®, and all gas heaters are at least Low NOx. Affordability combined with energy-saving capabilities means that this series has some of the top water heaters, not just from Rheem but from any brand.

With a GPM of 3.17 and wattage of 13,000, the RTEX-13 is ideal for a studio apartment or for a small family that only needs hot water for a single bathroom at a time. You’ll only need to wait around 15 seconds to receive the hot water.

RTEX-13 Model

Rheem RTEX 13

RTEX-13 is one of the best options if you want a budget, point-of-use water heater. It will meet your needs but is free from extras, which simplifies operation. For instance, the multiple-stranded wire makes connecting it to a power source easy. Its small size means it will fit in any home that has space for an indoor heater.

With a GPM of 3.17 and wattage of 13,000, the RTEX-13 is ideal for a studio apartment or for a small family that only needs hot water for a single bathroom at a time. You’ll only need to wait around 15 seconds to receive the hot water.

RTEX-18 Model

rheem rtex-18

For slightly more functionality, there’s the RTEX-18. Again, this is a point-of-use heater, but it does offer a slightly higher GPM of 4.4. This allows homeowners to use it for a single bathroom and kitchen faucet at the same time. Like the RTEX-13, it is compact, making it ideal for smaller homes looking to install an electric heater indoors. The low upfront cost and easy installation make this heater an especially cost-effective option.

An additional advantage of the RTEX-18 is its suitability for cold climates. It has advanced self-modulation technology to change the amount of power it uses according to demand. This means there are no fluctuations of temperature no matter where you live.

Professional Prestige Series

Rheem Performance Classic Series

Other high-end heaters are part of the Professional Prestige series. These have all the features of the Professional Classic series and more. Gas heaters have a high energy factor of 0.64 to 0.83, whereas all electric heaters have 0.93 for unbeatable efficiency. Many models are Energy Star rated or eligible for tax credits.

RTG-84DVLN Model

Rheem RTG-84DVLN

The RTG-84DVLN is an Ultra-Low NOx natural gas water heater. It has a very high energy factor of 0.82 and uses an all-copper heat exchanger. For a rise of up to 35 degrees Fahrenheit, it has a GPM of 8.4 and a 45-degrees Fahrenheit rise it offers a GPM of 6.7.

Some of the top features that the RTG-84DVLN shares with other RTG models include: 

  • Water Savings Setting. This allows you to save up to 1,100 gallons of water a year by reducing the flow of water until it reaches the right temperature.
  • Low Flow Activation. Provide your household with water when the demand is low.
  • Maintenance Notice Alerts. Ensure you receive maintenance on time. This notification will advise you to receive a checkup after 500 hours of use.

RTG-84XLN Model

Rheem RTG

The RTG-84XLN is another natural gas heater which can power a whole house. In addition to possessing all the above features, this model is energy star certified, 120 volts, and able to reach a whopping 8.4 gallons per minute. The outdoor version has freeze protection to withstand temperatures as low as -30 degrees Fahrenheit. 

RTG-95XLP Model

Rheem RTG-95XLP

Finally, we have a propane gas option: the RTG-95XLP. This powerful model offers a flow rate of 9.5 GPM to meet the needs of large families. Even though it is an outdoor model, it is Low NOx to be more environmentally friendly.


Where to Buy a Rheem Water Heater

You can find all of the models mentioned above in the Rheem tankless heater review for sale on Amazon. You’ll also find many other great choices from all five of the series. Lastly, if you want to see other tankless water heater brands before purchasing, be sure to check out our main review page.

So, if you’re looking to purchase one of the highest quality brands of water heaters check out Rheem’s top whole house model on Amazon here.

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David Trinh
David is an expert in all things plumbing, heating, cooling, and water treatment. He got his start in the plumbing business working on fixing all types of home improvement issues including water leaks, broken toilets, appliance installation, and more. Over time, he learned a ton about installing and choosing the correct water treatment products for homeowners.

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