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Rheem GNU100-200 - GNU100-200 Universal Ultra Low NOx Heavy Duty Water Heater, Natural Gas, 199,900 BTU, 100 gallon

Item: GNU100-200
MFR: GNU100-200
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Universal™ ultra low NOx is a family of commercial gas water heaters that are designed to fit into tight retrofit applications
  • Features & Benefits - The tighter the commercial retrofit, the more you will appreciate how the Universal's compact size and multiple water connections simplify ultra low NOx installations. Choose from 80% thermal efficiency models that range from 125,000 - 399,900 BTU/h and 82% thermal efficiency models that range from 199,900 - 270,000 BTU/h. All models have a maximum temperature setting of 180°F.
  • Space Saver Design - The short heights and narrow jacket diameters, plus the top, front and rear water inlets/outlets offer the ultimate in installation flexibility.
  • System Sentinel™ LED Diagnostic System - Our exclusive diagnostic system, with glowing LED lights, verifies system operation sequence by sequence.
  • Patented Technology - Universal's proprietary steel formulation, patented multi-flue design, combined with two coats of porcelain enamel, results in a superior heat exchanger design.
  • Ultra Low NOx Burner - The power assist burner design incorporates stainless steel multi-port burner tubes for long term ultra low NOx performance, less than 14 ng/J. A sight glass allows for burner observation. The entire design is removable and it is highly resistant to the effects of negative air pressure common in modern commercial buildings.
  • Base Rail Design - Provides for better handling when moving and positioning unit.
  • Low Profile Automatic Flue Damper - Low profile damper minimizes overall product height. Heavy duty vent hood supports are designed to withstand the rigors of installation.
  • Full-port, Full-flow Drain Valve - Factory installed brass drain valve allows for faster draining and servicing.
  • Direct Spark-to-Pilot Ignition System - Energy saving ignition that ignites pilot only when there is a call for heat.
  • Altitude Certifications - Universal ultra low NOx is certified up to 2,000 feet. High altitude certification for model GNU100-200(A) is 5,200 feet.
  • Patented Anode Rods - Anode design utilizes multiple magnesium rods to ensure corrosion resistance for a long tank life.
  • Warranty - 3-Year limited tank warranty
  • See Commercial Warranty Certificate for complete information.


NameRheem GNU100-200 - GNU100-200 Universal Ultra Low NOx Heavy Duty Water Heater, Natural Gas, 199,900 BTU, 100 gallon
Gemaire Item NumberGNU100-200
Manufacturer Product NumberGNU100-200
SKU - PIM Number1404399737011
ERP Number344682
Unit of MeasureEACH
Weight780.0 Pound (lb.)
Length30.2 Inches (in)
Width30.2 Inches (in)
Height73.0 Inches (in)
Hazardous MaterialNo
EPA Cert RequiredNo
Country of OriginMEX
BTU Input199900
Ignition TypeHot Surface/Direct Spark
Capacity Gallons100
CertificationsAHRI Certified, High Altitude Certification
CompositionProprietary steel
Fuel TypeNOx
Gas TypeNatural Gas/LP
Maximum Pressure (PSI)150
Maximum Temperature180°F (82.2°C)
TypeTanked - Gas
Warranty Offered3 Year Limited Tank
Energy Star RatedNo
Product FamilyGNU100
GEM - Case Quantity