Rheem Rtex 18: Is It The Best Electric Tankless Water Heater

Bathroom, Beginner Info, Tankless Water Heater

Rheem Rtex 18
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Rheem Rtex 18: Well, in this post, I would be walking you through the nuts and bolts of Rheem Rtex 18 in order to help you make an informed buying decision.

Moreover, I would be throwing light on various aspects of Rtex 18 to help you clear your doubt before you make a purchase decision.

Lastly, I would be responding to the queries related to Rheem Rtex 18 Reviews so that you can reap maximum benefits from this post.

Does it make sense?

So, without any further ado, let’s begin…

Rheem Rtex 18 Tankless Water Heater Review

The Rheem Rtex 18 is definitely one of the most sought and popular offerings from the brand Rheem.

In order to provide our readers with the most authenticate and genuine review of Rheem Rtex 18, I along with my editorial team came up with an idea to reach out to the current users of this product who are our clients as well.

No one gives genuine feedback better than them.

What actually we did is formulated a questionnaire that was the outcome of the Rheem Rtex 18 “FAQs” that we’ve received from our clients over a period of time.

[Related] Best Budget Rheem Tankless Water Heater Review

Well, before we move further, let me tell you, most of the important queries related to Rheem Rtex 18 have been answered in our “FAQs” in order to help you clear most of your doubts before you make a purchase decision.

To be honest, the response that we got about RTEX-18 from our clients was mesmerizing, indeed.

Most of our clients were in praise of the quality, performance, and longevity of the product.

When asked whether you’ll recommend it to your friends and families or NOT.

98.35 percent of our clients nodded their heads with a big “YES”, insane, isn’t it?

If I’ve to defined RTEX-18 in one single sentence, then I would ONLY say that it is a complete package and comprise almost all the essential ingredients that you might be looking for in your favorite electric tankless water heater.

Cutting long-story-short, and coming back straight to Rheem Rtex 18 review, it is equipped with a brass heat exchanger and rugged copper built to deal effectively with harsh water conditions.

On top of it, the little beast is equipped with 2 heating chambers with 18 kW full power.

The Rheem RTEX-18 possesses a simple and slim design.

Not only is it meant to last longer but also delivers high performance.

In an ideal condition, the Rheem RTEX-18 is capable of providing a water flow of 4.4 GPM which is definitely one of the best for both small and medium households.

The small and compact size makes it possible to get installed in any nook & corner of your house.

Furthermore, the 240V is a standard voltage and doesn’t require any modification in your electrical system.

Unlike a conventional water heater where heat loss is very prominent, the Rheem RTEX-18 doesn’t have any standby heat loss.

As a result, the RTEX-18 has very low energy consumption and runs only when needed.

It includes almost all the user-friendly features that will help in operating the unit without any hassle.

In fact, an on-unit control system is present right in place for easy temperature adjustments.

You may be astonished to know that it can easily cover two bathrooms in any kind of weather condition.

And, the best part is, it comes with a considerable low amperage 75 A which stuck a great balance between electric heater without an electric grid update.

Trust me, the Rheem RTEX-18 is definitely one of my favorites and I’ve been using it for quite some time now.

Definitely, it’s a perfect choice for your homes, condos, apartments, hospitals, boats, offices, hotels, and restaurants.

And, if you’re like me who loves eco-friendly products then definitely, the Rheem RTEX-18 is for you.

I personally like the fact that the operation is quiet and calm, and you’ll not hear any clicking relays.

It is capable of providing an endless supply of hot water on demand for small and medium homes.

Well, the Rheem RTEX-18 is enough for all my family’s hot water requirements including dishwasher, kitchen sink, laundry sink, bathroom sink, and bathtub.

For the convenience of end-users, the unit also comes with a mounting/wiring diagram.

To be honest, the brand Rheem doesn’t need any introduction and comes with a highly efficient customer service tech, and I can say this confidently just because I’ve taken the support team help a couple of times, and it not only matched but exceeded both my expectation and experience.

I own a 4 bedroom apartment, and many of you would be astonished to know that the hot water takes a max of 2 minutes to reach the farthest bathroom.


  • Equipped with digital thermostatic control and LED display
  • Heat exchanger is made up of brass
  • Capable of providing a flow rate of 4 GPM
  • Could be a perfect fit for both small and medium house owners
  • Installation process is quick, easy, and newbie-friendly
  • Equipped with innovative and advanced techonologies including self-modulation
  • Also, comes with robust copper immersion heating elements
  • Highly energy-efficient as compared to a traditional water heater
  • 10-years of heat exchanger warranty


  • A low amperage of 75 A
  • Affordable, reliable, and durable electric tankless water heater
  • Quick, easy, and newbie-friendly installation process
  • Uniquely designed, compact, portable, and easily transportable
  • Doesn’t require huge space for installation
  • Comes with on-unit controlling feature


  • Not the BEST choice for big households

What Our Client’s Say About Rheem Rtex 18

To be honest, a majority of our clients were quite positive about the Rheem Rtex 18.

But, at the same time, there were outliers who weren’t happy with this product.

So, let have a quick look at both the positive and negative aspects of Rheem Rtex 18.

My clients were quite vocal about the user experience and convenience that Rheem Rtex 18 brings to the table.

The quiet operation and ability to provide hot water on the end-users volume choice were simply the talk of the town.

All you need to do is to choose the temperature and the rest would be taken care of by the heater.

Also, our clients were impressed with the fact that a single unit is enough for providing hot water to a dishwasher, kitchen sink, laundry sink, bathroom sink, and bathtub which clearly depicts the capacity of the unit.

Another positive point of the unit is the ease of installation so even though you’re a first-time buyer you wouldn’t find the installation process cumbersome and time-consuming.

Our clients were ready to recommend this unit to their friends and families which clearly shows the trust and confidence that they possess in the product.

The drastic decrease in the water heating bills also surprised quite a few of our clients when they replaced their conventional tank-style heater with Rtex 18.

The Rtex 18 ability to deliver scalding hot water in less than 30 seconds to both kitchen and bathroom also was a reason for its buy.

However, the Rtex 18 has its own share of cons that is equally important for you to be aware of.

Some of our clients complained about the frequent occurrence of E5 errors.

Also, I heard a few saying that they received a defective unit with leaking in tubes.

Just forget to mention, quite a few of our clients were satisfied with the deduction in their water heating bills, their expectation was much more.


As promised to our clients and readers of this blog, here we come with some interesting answers to the questions that we’ve received so far.

Is Rtex 18 worth it?

Definitely, it’s worth your time and money.

In layman’s terms, it comprises almost all the essential ingredients that you might be looking for in your favorite water heater.

The Rtex 18 is equipped with advanced and innovative technologies to provide its users a superlative experience.

Its unique design, robust construction, and ability to get installed in small and compact space makes it a perfect choice for small and medium households.

As compared to a conventional tank-styled water heater, this little beast is meant to last longer as well as reduce electricity bills drastically.

Where can I find Rheem Rtex 18 wiring diagram?

I’m attaching a wiring diagram of an electric tankless water heater, and I hope it will serve your purpose.

Rheem Rtex 18 wiring diagram

Wrapping Up | Rheem Rtex 18 Tankless Electric Water Heater Review

First and foremost, I would like to thank you for being with us till the end.

Secondly, I would like to bring to your notice that I along with my core team have put loads and loads of effort into coming up with this idiosyncratic superlative comprehensive buying guide on Rheem Rtex 18 Tankless Electric Water Heater Review.

And, in case, you liked our effort and want to appreciate us then please do share this piece of information with like-minded people and the ones who are in need of it.

After all, sharing is caring, isn’t it?

Cutting long-story-short, the Rheem Rtex 18 is definitely one of the best electric tankless water heaters available on the market, and I couldn’t find any reason why my clients shouldn’t invest in it.

We wholeheartedly recommend Rheem Rtex 18 as we find it a worthy investment.

Do let us know in the comment section your view on Rheem Rtex 18.

That’s all, as of now :):)

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