Rheem RTG-64XLN 6.4 GPM Low NOx Outdoor Tankless Natural Gas Water heater

Rheem RTG-64XLN Outdoor Tankless Water Heater

Rheem is one of the industry leaders and is a trusted name in the world of tankless water heaters and home appliances. Therefore, it is no surprise that the Rheem RTG-64XLN Outdoor Tankless Water Heater has quickly become a best-selling, natural gas tankless heater. It offers a simple and straightforward design that boasts a stainless steel cabinet to protect its components and internal circuitry. Energy Star’s Seal of Approval is prominently displayed on the front cabinet door. According to Rheem, buyers save an average of $200.00 annually on their energy bills with this unit.

What distinguishes the Rheem RTG-64XLN from its competition is the fact that it is designed to be installed outdoors. It can be mounted on almost any exterior surface or wall. You will have the option of hardwiring it into your home’s current electrical system, or it comes an option plug that enables it to be used with any 120 volt outdoor power source. Rheem recommends hardwiring this model when possible, but it will require professional assistance to do so.

Read on to find out more about what the Rheem RTG-64XLN Outdoor Tankless WaterHeateroffers!

Key Features

  • This Rheem model is powered by natural gas or propane.
  • It is designed to be installed outdoors.
  • It has low nitrogen oxide emissions ““ as independently certified by GAMA and Energy Star.


  • With the ability to raise water temperature 35 degrees, the Rheem RTG-64XLN Outdoor Tankless Water Heater offers an astonishing flow rate of 6.4 gallons per minute ““ making it suitable for the largest applications.
  • Included in your purchase of this model is 10 feet of thermostat wire.
  • A UMC-117 remote control allows you to adjust the hot water temperature as needed without having to go outside.


    • It cannot be installed indoors.

      Product Review

      At the time of this writing, 84% of reviewers have given the Rheem RTG-64XLN Outdoor Tankless Water Heater a five star rating ““ a feat that is almost unheard of! Another 8% have rated it four stars. What is making this model so popular with buyers? Here are a few basic stats on the RTG-64XLN:

      • It has an industry first minimum flow rate of .26 gpm and a minimum activation flow rate of .40 gpm.
      • It has high altitude capabilities meaning that it can be used up to 9,800 feet above sea level, and no chip is required.
      • This model is environmentally friendly, and its Ultra Low NOx burner surpasses the requirements set forth by SCAQMD Rule 1146.2.

      When the temperature rise is 35 degrees Fahrenheit, the Rheem RTG-64XLN Outdoor Tankless Water Heater offers an impressive flow rate of 6.4 gpm. It is the first tankless water heater in the world to come equipped with a heat exchanger crafted entirely from copper. The copper does an exquisite job of keeping the water heated. Furthermore, it minimizes the water flow delay and allows users to enjoy more hot water right off the bat. Since it is an outdoor model, the entire model is wrapped in a unique film that protects the exchanger and keeps it from rusting.

      One feature that users have soundly praised is the unit’s remote control for the temperature. Whether you want to adjust the temp from across the lawn or inside your house, this battery powered remote will allow you to do so. This feature has been especially appreciated by those who live in frigid climates.

      It is important to note that the Rheem RTG-64XLN Outdoor Tankless Water Heater can ONLY be installed outdoors. It is powered by natural gas, so it requires plenty of room to vent. The internal, low NOx condensing system does an excellent job of minimizing the amount of fumes it puts out, but it does not break down the fumes enough to allow this model to be installed indoors. Rheem strongly discourages users from attempting to put any type of cover on this unit after it has been installed.

      As with its other tankless water heaters, Rheem offers an excellent warranty on the RTG-64XLN. The heat exchanger is covered by a 12 year warranty, and parts and labor are covered by a 5 year warranty. The unit must be installed by a licensed professional for the warranties to be honored.


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      Thank You For Reading

      For the right household, the Rheem RTG-64XLN Outdoor Tankless Water Heater has a lot to offer from one of the best brands in the industry. Because it is a gas powered model, its efficiency rating peaks at .84; however, it has a solid design, is backed by a strong warranty, and is capable of servicing up to 4 faucets at once. Reading consumer written reviews is one of the best things you can do before buying a new product, and with the reviews that this Rheem model has earned, it seems like an excellent investment in your home.