RTGH-90XLN Outdoor Natural Gas Condensing Tankless Water Heater

Designed for continuous hot water for 2-3 bathroom homes, the Rheem RTGH series, including the RTGH-90XLN outdoor condensing tankless water heater, is an ultra low NOx, natural gas fired water heater.

Rheem’s 90 year legacy of water heating innovation is built into every water heater Rheem manufactures.

  • Up to .94 EF with stainless steel condensing heat exchanger
  • Recirculation Pump Kit-Ready – Quickly pairs with our Recirculation Pump kit to provide instantaneous hot water at the tap
  • Self-diagnostic system for easy installation and service
  • Built-in electric blower


  • Models H95, H90, and H84
  • Models available in 199,000 BTU/h, 180,000 BTU/h, and 157,000 BTU/h
  • High Temperature Chip Option – Increases the output temperature from 140 ºF max to 185 ºF max.
  • Up to 94% efficient



  • Parts Warranty – 5 Years
  • Labor Warranty – 1 Year
  • Heat Exchange Warranty – 5 Years