Universal™ is a family of commercial gas water heaters that are designed to fit intotight 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 installations. Choose from 80% thermal efficiency models that range from 98,000-399,900 Btu/h and have maximum temperature setting of 180 degrees Fahrenheit.

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.

Stainless Steel Burners

Precision burners, raised port design, are formed from high chromium stainless steel. Each burner assembly slidesout like a drawer for quick inspection and maintenance.

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

Up to 5,000 feet for natural gas and 2,000 feet for LP; with high altitude certification kit, up to 8,000 feet.

Patented Anode Rods

Anode design utilizes multiple magnesium rods to ensure corrosion resistance for a long tank life.

50 G50-98 98,000
75 G75-125 125,000
82 G82-156 156,000
76 G76-180 180,000
35 G37-200 199,900
76 G76-200 199,900
91 G91-200 199,900
100 G100-200(A) 199,900
40 G72-250(A) 199,900
100 G100-250(A) 250,000
100 G100-270(A)  250,000
42 G72-300(A) 170,000
85 G85-300(A) 300,000
100 G100-310(A) 300,000
65 G65-360(A)  310,000
65 G65-400(A) 360,900
85 G85-400(A) 399,900
100 G100-400(A) 399,900


GN75-125 125,000
82 GN82-156 156,000
35 GN37-200 199,900
76 GN76-200 199,900
91 GN91-200 199,900
100 GN100-200(A) 199,900
72 GN72-250(A) 250,000
100 GN100-250(A) 250,000
100 GN100-270(A) 270,000
65 GN65-360(A) 360,000
100 GN100-400(A) 399,900
75  GNU75-125 125,000
82 GNU82-156  156,000 
35 GNU37-200 199,900
76 GNU76-200 199,900
91 GNU91-200 199,900
100 GNU100-200(A) 199,900
40 GNU72-250(A)  250,000
100 GNU100-250(A) 250,000
100 GNU100-270(A) 270,000
65 GNU65-360(A) 360,000
100 GNU100-400(A) 399,900

(A) Indicates available ASME Model
G100-200 G100-250 G75-125 G76-200-1 G85-400 GN75-125 GNU75-125

  • Space-saving tank design
  • 98,000 - 400,000 BTU/Hr.
  • System Sentinel™ LED diagnostics
  • Multi-flue tank design


Brochure (US and Canada)
Brochure - Low NOx
Revit Model (G37-G100)
Revit Model (Low NOx - GN37-GN100)
Revit Model (Ultra Low NOx - GNU37-GNU100)
Specification Sheet - Low NOx (US)
Specification Sheet - Ultra Low NOx (US)
Specification Sheet -Standard (US and Canada)
Use and Care Instructions (US and Canada)
Warranty Information


United States
Tank Warranty: 3 Years
Parts Warranty: 1 Year

Tank Warranty: 3 Years
Parts Warranty: 1 Year

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  • 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.