Xtreme™ is a family of high-input, fast recovery commercial water heaters that complies with Low NOx Emissions

Benefits – Xtreme is an advanced line of fast recovery commercial gas water heaters. These products can deliver up to 756 gallons per hour at 100 degree F rise. The small jacket diameter makes it a popular choice for retro fits and it is a versatile choice for new construction. Models range from 500,000-715,000 Btu/Hr, with a maximum temperature setting of 180 degrees Fahrenheit.

Space Saver Design – Xtreme maximizes installation adaptability by offering models with front and rear inlet/outlet water connections. Short heights and small jacket diameters result in greater installation flexibility.

System Sentinel™ LED Diagnostic System – Our exclusive diagnostic system, with glowing LED lights, verifies system operation sequence by sequence.

Patented Multi-Flue Tank Design – Proprietary steel formulation, patented multi-flue design, and two coats of high temperature porcelain enamel maximize corrosion resistance and result in a superior heat exchanger design.

Automatic Flue Damper – Low profile design minimizes overall product height. Heavy duty vent hood supports are designed to withstand rigors of installation.

Specialized Burner Assembly – Each model features five premix burners mounted into a metal face plate and sealed with a Viton gasket. Patented “quick release” manifold for easier service.

Direct Spark-to-Pilot Ignition System – Energy saving ignition that ignites pilot only when there is a call for heat. Round Premix Burners Precision burners are formed from high chromium stainless steel.

Low NOx Emissions – GX90-550 and GX90-640 meet Low NOx emissions of less than 40 ng/J.

Full-port, Full-flow Drain Valve – Factory installed brass drain valve allows for faster draining and servicing.

Altitude Certifications – Standard Natural and LP models are certified up to 2,000 feet. High altitude models, 8,000 feet.

Anode Rods – Patented design utilizes multiple magnesium rods to ensure long life and corrosion resistance.



 90  GX90-550(A) 550,000 NAT
90 GX90-640(A) 640,000 NAT
90 GX90-715(A) 715,000 NAT
90 GX90-500(A) LP 500,000 LP
90 GX90-600(A) LP 600,000 LP
90 GX90-680(A) LP 680,000 LP


  • High-input – 550,000 - 715,000 BTU/hr.
  • Available in 90 gallon capacity
  • Space-saving tank design
  • Low profile automatic flue damper

Energy Guide Details


  • HLW on selected models
  • AHRI




Tank Warranty - 3 Years

Parts Warranty - 1 Year

KwikComfort® Financing can help make your purchase even easier.
Ruud makes it easy to find a financing option that works for you! With many options and benefits available, KwikComfort Financing is the best way to get the home comfort you need without the wait.

  • Applications made easyWe'll help you avoid lengthy contracts, headaches and hassles.
  • Kwik credit decisionsYou'll get an answer to your application within minutes.
  • Fast credit for the futureFinance your Ruud equipment and anything you want to add later.
  • Reduced interest/fixed paymentsGet low interest and fixed monthly payments until the purchase is paid.
  • Minimum monthly paymentTake advantage of convenient monthly payments that fit your budget.
  • Deferred interest/no interestEnjoy interest-free payments as long as the balance is paid by the due date.