#1 Home Improvement Retailer

Customer Reviews for Rheem Performance 18 kW 3.51 GPM 240-Volt Self-Modulating Electric Tankless Water Heater

Internet #300800620

Model #RETEX-18

Store SKU #1002624315

  • Electric tankless water heater provides consistent hot water
  • Energy and cost savings of up to 34% in whole-home installations
  • Tankless water heater requires 2 x 40 AMP double pole breakers

Customer Reviews

  • 3.9
    out of 2,405 reviews
  • 61% recommend this product
Filter by:
Showing 1-30 of 2,405 reviews
by
  • Verified Purchase
by
  • Verified Purchase
by
  • Verified Purchase
For me, convienence was important. I liked having demand heated water in my home and I lived alone so it supplied all my needs for my 1400 sq.ft.home. It was ordered online and delivered the next day to my home, couldn’t have been easier!
by
Response from RheemSep 12, 2024
Hello,

Thank you for the 5-star review! Rheem is happy to hear that you found the right unit for you!

Isaiah rheem
  • Verified Purchase
First one lasted a year, second lasted 3 weeks.. on to number 3. We’ll see!!
by
Response from RheemSep 11, 2024
Hi,

We are sorry to hear about the issues you’ve had with your tankless water heaters. It must be really frustrating to deal with such frequent replacements. Hopefully, the third one will be more reliable and last much longer.

If you continue to experience problems, it might be worth reaching out to customer service for further assistance or to discuss potential alternatives. Sometimes, there might be underlying issues that need to be addressed to ensure the longevity of the unit. Please call, 800-543-6163 between the hours of 8 A.M. and 5 P.M. EST Monday through Friday.


Derius rheem
  • Verified Purchase
Great product , space saver I haven’t had any issues so far
by
Response from RheemSep 11, 2024
Hello Alfredo,

It is great to hear that you are enjoying your new Rheem Tankless Electric Water Heater! Thank you for your 5-star review!
 
Isaiah rheem
  • Verified Purchase
It's a great unit when it works
4 Year old unit. When it's working it's absolutely fabulous. Unfortunately, when something goes off kilter it is impossible to diagnose. There is scant information regarding the actual errors you may encounter leaving you at the mercy of calling a professional. Worse, it has a tendency to produce H103 errors (High limit switch) but there seems to be no way to find out about said switch. All references online are for a similar model that does not match the way this one is laid out.
by
Response from RheemSep 10, 2024
Hello Trish,

Thank you for your review and feedback. Our goal is always to provide the best product and service possible to our customers. We will certainly use your feedback to help current and future customers have a better experience and product. If you need assistance with your water heater, please free to reach out to our Technical Support Team at 866-279-4566 between the hours of 7 A.M. and 7 P.M. CST and one of our experienced analysts will be happy to assist you.

Isaiah rheem
    Do Not Buy This For Seasonal Use!!!
    This heater is not for seasonal use despite being sold as such. IT DOES NOT HAVE A DRAIN OUTLET like other Retex models so it can't be winterized. I spent over $500 for the unit plus plumbing and heating install and now have to pay to have it uninstalled. I am left with a useless heater and Rheem refuses to allow a return so I am out the money. I will not be buying from Rheem again.
    by
    Response from RheemSep 5, 2024
    Hi,

    We are really sorry to hear about your experience. It must be incredibly frustrating to invest so much money and effort into a product that doesn’t meet your needs, especially when the service isn’t accommodating.

    Have you tried reaching out to customer service for assistance? Sometimes, they can help mediate issues. Please call 800-543-6163 between the hours of 8 A.M. and 5 P.M. EST Monday through Friday.

    Derius rheem
      Love how the water warms instantly and love the space I know have versus the round cylinder water heater best investment I’ve made
      by
      Response from RheemSep 5, 2024
      Hello Milla,

      Rheem thanks you for the 5-star review! We are glad to hear that you are experiencing the benefits of a tankless electric water heater.

      Isaiah rheem
      • Verified Purchase
      Absolute 100% Junk
      Failed within 4 months, just outside the HomeDepot warranty. Manufacturer warranty a joke, said I would have to test the system or they won't honor the warranty. So if you're not an electrician you have to hire one to come out and test the unit which in most cases will cost you more than this unit is worth. These are sold under several names, Rheem, Ruud, Richmond, ecosmart, Eemax, and Friedrich - Don't buy one, they are all JUNK !!
      by
      Response from RheemAug 30, 2024
      Hi,

      Thank you for your feedback. We’re very sorry to hear about the issues you’ve experienced with your water heater and the challenges with the warranty. We understand how frustrating this must be. Please reach out to our customer service team for further assistance. We’re here to help resolve this for you. Please call 866-279-4566 between the hours of 7 A.M. and 7 P.M. CST at your earliest convenience.

      Derius rheem
        Doesn't last- finnicky!
        Bought the first one and only lasted a few months. Purchased a second one and it lasted 5 weeks. Nothing to do with electricity. Our plumber/electrician checked everything and looks like due to some flow sensor. Not worth the money or headache trying to fix it. Plus help and troubleshooting on the website is a total joke
        by
        Response from RheemAug 30, 2024
        Amber,

        Thank you for your feedback. We’re very sorry to hear about the repeated issues you’ve experienced with your water heater. We understand how frustrating this must be. Please reach out to our customer service team for further assistance. Please call 866-279-4566 between the hours of 7 A.M. and 7 P.M. CST at your earliest convenience.
        Derius rheem
          by
          • Verified Purchase
          Used item instead of new
          Rheem RTX 13 KW. Bought new. Packaged in sturdy box. But the product box was obviously crinkled, and the plastic wrapper was opened. The Heater has some scuff marks on it which indicate previous use and installation…. and there was still water dripping out of it. So Home Depot sold me, instead of new…a used item which was previously returned. I’m going to install it and if it doesn’t work, I will be returning it. Come on Home Depot…. You’re better than this nonsense.
          by
          Response from RheemAug 27, 2024
          Hi,

          We are sorry to hear about your experience with the water heater you have reviewed. It sounds frustrating to receive a product that appears to have been used, especially when you expected it to be new.

          If you encounter any issues with the installation or performance, returning it is definitely a good idea. You might also consider contacting customer service to report the condition of the item and request a replacement or refund. They should be able to assist you in resolving this issue.

          If you need help regarding this situation, please contact HomeDepot.com customer service department at 1-800-466-3337 any day between 6 A.M and 2 A.M. EST. Home Depot Customer Service will be able to assist you with this issue or transfer you to your local store for more assistance.


          Derius rheem
            by
            • Verified Purchase
            by
            • Verified Purchase
            Just don’t.
            This is the “new” version of the one I purchased in 2022. Before the warranty was expired, it had already gone so bad it needed replaced. Since it was under warranty, Rheem sent the “new” version. You have to go through troubleshooting steps and then they ship out the replacement. That was February 2024 and I was without hot water for 2-3 weeks. It is now mid August and again without hot water for almost a month because we have to troubleshoot and currently waiting for the second parts shipment.
            by
            Response from RheemAug 20, 2024
            Hi,

            We are truly sorry to hear about the ongoing issues you’ve been experiencing with your water heater. It’s certainly not the experience we want customers to have. We understand how frustrating it can be to be without hot water for extended periods of time, especially while waiting for replacement parts. Your feedback is valuable, and we’ll do our best to improve our products and services. Thank you for your patience and understanding.


            Derius rheem
              • Recommended
              Fine performance for a smaller living space
              by
              Response from RheemAug 20, 2024
              Dear Rob,

              We’re glad to hear that the Performance Electric Tankless Water Heater is working well in your smaller living space. We appreciate your positive feedback. Thank you for choosing Rheem!


              Derius rheem
              • Verified Purchase
              by
              • Verified Purchase
              Works great! Easy to adjust temperature.
              by
              Response from RheemAug 2, 2024
              Hello JG,

              Thank you for the 5-star review! We are happy to hear that you are enjoying your new Rheem Tankless Electric Water Heater and it's easy of use controls.

              Isaiah rheem
              • Verified Purchase
              by
              • Verified Purchase
              Almost burned the house
              We had ours just about 2 years and it stopped working one day. When we removed the cover the top of the heating elements had burned and there was a flash mark on the drywall. When we contacted Rheem they told us that they would not honor the warranty because of lack of maintenance, even though it says in the manual that no maintenance is needed. This unit is dangerous and I do not recommend buying it.
              by
              Response from RheemAug 9, 2024
              Hi,

              We are sorry to hear about your experience with the new water heater you purchased. It sounds frustrating and concerning, especially with the safety issue you described.

              This model is generally praised for its energy efficiency and consistent hot water supply. However, your experience highlights a significant issue with the heating elements and the warranty policy. It’s important for potential buyers to be aware of both the positive and negative aspects before making a decision.

              If you’re looking for alternatives, please call 800-374-8806 between the hours of 8 A.M. and 5 P.M. EST Monday through Friday.


              Derius rheem
                • Recommended
                In-line water heater installed easily and functions well. In a low usage area, it is more efficient than a tank heater.
                by
                Response from RheemAug 2, 2024
                Hello,

                Rheem thanks you for the 5-star review! We hope that your new Rheem Tankless Electric Water Heater serves you well for many years to come!

                Isaiah rheem
                • Verified Purchase
                warranty information
                What a beating killer watch work fine. Got it one morning. It's not working you weren'the warranty says 5 years 1 year on part. What's the sense of a 1 year part where you need to replace the unit? Home depot needs to check. The warranty offered by the products that they offer in customers. Some of the warranties that are offered by these products.I like green or some kind of rip-off.Why should I have to replace a part and pay for it when the unit is only a year old
                by
                Response from RheemAug 9, 2024
                Victor,

                Thank you for this 4-star review! We are sorry to hear about your frustrating experience with the water heater you have reviewed. It must be disappointing to have the unit fail so soon and face issues with the warranty.

                This model is generally praised for its energy efficiency and ability to provide consistent hot water. However, your experience highlights potential reliability issues and concerns with the warranty policy.


                Derius rheem
                  It only works for 3-5 minutes and then goes off, it’s like it needs for water flow even know the house has very good water flow
                  by
                  Response from RheemAug 9, 2024
                  Hi,

                  We are sorry to hear about the issues you’re experiencing. It sounds frustrating to have the water heater shut off so quickly. This could be due to a variety of reasons, such as a sensor issue or a problem with the flow rate detection.

                  If you haven’t already, we recommend checking the user manual for troubleshooting tips or contacting our Technical Support team for further assistance. Please call, 866-279-4566 between the hours of 7 A.M. and 7 P.M. CST at your earliest convenience.


                  Derius rheem
                  • Verified Purchase
                  I bought a different brand and it stopped working within the first 3 months but so far so good with the product. It takes some time to get hot, but when it does, it's HOT! I hope it continues to work.
                  by
                  Response from RheemAug 8, 2024
                  Annette,

                  We are glad to hear that this water heater is working well for you so far, Annette! It sounds like it’s doing a great job once it heats up. I understand your concern given your previous experience. Fingers crossed that this one continues to perform reliably for you!


                  Derius rheem
                  • Verified Purchase
                  Junk
                  The first one did not work. The replacement did not work. Even if you get your money back, how many days do you want to spend without hot water, having to pay to install, uninstall, time and gas to drive back and forth.
                  by
                  Response from RheemAug 8, 2024
                  Dave,

                  Thank you for this review. We are really sorry to hear about your frustrating experience with the tankless water heater. It’s incredibly inconvenient to deal with multiple faulty units, especially when it means being without hot water and incurring additional costs for installation and travel.

                  For assistance with your water heater and issues arising from it, please call 866-279-4566 between the hours of 7 A.M. and 7 P.M. CST.

                  Derius rheem
                    by
                    • Verified Purchase
                    only last 1 year
                    System only last 1 year, I bought in MAY 2023 and now July 2024 and the Thermistor is not working. Water is no longer hot . I am disappointed
                    by
                    Response from RheemAug 8, 2024
                    Hi,

                    We are really sorry to hear that your tankless water heater only lasted a year before the thermistor stopped working. It’s definitely disappointing when a product doesn’t meet expectations, especially something as essential as a water heater.

                    If you haven’t already, you might want to check if it’s still under warranty or contact customer service for a possible repair or replacement.

                    If you need any advice on what to do next or have any other questions, please call 800-374-8806 between the hours of 8 A.M. and 5 P.M. EST Monday through Friday.


                    Derius rheem
                      This was a replacement for the exact model that lasted only 4 years. The supposed lifespan is up to 15 years. We are 2 people in our house, so it’s not over used. We have hard water that probably caused the short lifespan. The remedy would be a water filtration system, so cost might be the same! If you are willing to wait 30-45 seconds for hot water, then I recommend using this unit.
                      by
                      Response from RheemJul 23, 2024
                      Hello Nana,

                      Thank you for the 5-star review and for choosing Rheem for your home once more! Hard water can indeed affect the average lifespan of a water heater, tank and tankless. Performing periodic service and/or water treatment would help grant the unit a longer lifespan. If you never need help or just have questions about your new Rheem Tankless Water Heater, never hesitate to reach out to Rheem Tankless Electric Support at 800-374-8806 or eco.support@eemax.com.

                      Isaiah rheem
                      • Verified Purchase
                      Easy to adjust temp. Heats up pretty fast. It meets my expectations. I’ve had it for a week and I already love it!
                      by
                      Response from RheemJul 22, 2024
                      Hello,

                      Thank you for the wonderful 5-star review! We are glad to hear that you are enjoying the features and performance of your new Rheem Water Heater.
                       
                      Isaiah rheem
                      • Verified Purchase
                      Showing 1-30 of 2,405 reviews

                      Frequently Bought Together

                      Best Seller
                      +
                      +
                      Price:
                      $405.22

                      Compare Similar Items

                      current item

                      Wattage (watts)

                      18000 W

                      27000 W

                      19200 W

                      36000 W

                      Required Volt Connection

                      240 volt

                      240 volt

                      240 volt

                      240 volt

                      Application Type

                      Residential

                      Residential

                      Residential

                      Residential

                      Indoor/Outdoor

                      Indoor

                      Indoor

                      Indoor

                      Indoor

                      Water Heater Features

                      Wall Mounted

                      Wall Mounted

                      Digital Display, Freeze Protection, Overheat Protection, Wall Mounted

                      Digital Display, Freeze Protection, Overheat Protection, Wall Mounted