Learn About Rheem Tankless Water Heaters

Rheem Tankless Gas Water Heaters

With today's rising energy costs and environmental awareness in mind, Rheem has met and exceeded the expectations of home and business owners for new water heating solutions. Welcome to Rheem tankless water heaters.

Rheem tankless water heaters combine new technology and functionality in an innovative way to heat water. The result - you now have a greater choice of award-winning Rheem products designed to give you comfort. Our tankless water heaters are designed to enhance your lifestyle, utilize advanced technology for energy efficiency, and supply a continuous flow of low cost hot water whenever and wherever you need it.


Since our tankless products only use energy to heat water as it is needed, no energy is wasted while there is no demand for hot water. In addition, our tankless products put you in complete control over your water temperature with a precise digital controller. A touch of your fingertip can adjust the maximum water temperature up or down to the perfect comfort level that's just right for you. Moms love this feature because it prevents water from getting too hot for their children. These features plus many more add up to pleasant lifestyle and considerable savings on your energy bill.

Features & Benefits

  • Continuous hot water on demand – Tankless water heaters provide a steady flow of hot water whenever and wherever you need it.
  • Compact, space saving design – Our indoor and outdoor tankless water heaters are just over 2 feet tall, weigh 75 pounds or less, and attach to an interior or exterior wall.
  • Energy Efficient – Rheem tankless gas water heaters are very energy efficient. To calculate your estimated energy, please visit our tankless energy savings calculator page.
  • Indoor and outdoor models available – with a variety of propane (LP) and natural gas models for added choice and convenience.
  • Condensing or Non-Condensing models – Rheem offers a variety of models that feature 94% efficient stainless steel condensing heat exchanger, and models that feature an 82% efficient copper heat exchanger.
  • Environmentally-friendly – Our tankless products meet low NOx emissions standards (SCAQMD rule 1146.2) because of their advanced operational design and high efficiency.
  • High altitude efficiency – Rheem offers unique technologies for efficient tankless water heater operation up to and above 9,000 feet.
  • Digital display – All Rheem tankless models have a digital display that show temperature setting and maintenance codes.
  • Remote controls – all tankless models include a digital remote control with a maximum temperature setting of 140 degrees F. All remote controls require 18 AWG, 2 conductor thermostat wire that is sold separately in a variety of lengths.
  • Additional remote controls – Additional bath remote controls are available for all tankless models. These additional remote controls add convenience to a whole home tankless system by enabling the user to change the output temperature of their water heater from multiple locations.
  • Worry-free operation – Our award-winning tankless designs feature exclusive safety features including: - built-in self-diagnostic program - advanced sensors that prevent overheating - automatic shut-off system in the event of an error.
  • Self-diagnostic program – Our tankless water heaters use smart technology. The built-in self-diagnostic program displays maintenance codes when necessary. In the event an error is detected in the tankless unit, an error code will be displayed on the digital controller for quick reference and troubleshooting.
  • Large hot water volumes – Rheem tankless water heaters can be combined in several combinations to accommodate any hot water need. All models are manifold capable (up to 20 units) with a modular controller. With Rheem's EZ-Link technology, 2 units may be combined using a single EZ-Link communication cable.
  • Commercial and Hydronic – Rheem tankless water heaters can be upgraded for high temperature (up to 185F) applications such as Commercial or in home heater with forced air hydronic air handlers.
  • Built-in electric blower and 120V power cord - Inclusive on all indoor models.
  • Stainless steel venting – Non-condensing models require manufacturer approved concentric stainless steel venting for safe, efficient operation and extended life. Standard water heater vent material is inadequate for safety reasons.
  • PVC venting – Rheem Condensing tankless water heater models can be vented with PVC or approved Polypropylene venting material
  • Patented Guardian OFW™ Overheat Film Wrap – Patented safety feature that offers unsurpassed protection in the event of a breach of the tankless water heater’s heat exchanger. This device consist of a polyethylene film wrap embedded with carbon trace resistor that is constantly monitored by the control board. The OFW surrounds the tankless water heater’s heat exchanger and allows Rheem to have the best clearance to combustibles in the industry, just ½” from the sides and 0” on the rear. No other tankless manufacture offers the degree of protection provided by the Rheem Guardian OFW ™.

Please note - Proper gas pressure and volume must be ensured to supply any tankless water heater.  Rheem models feature capacities up to 199,900 BTU and reqiure a minimum gas line size of 3/4-inch.  Retrofit applications may require upgrades to the gas supply lines.