A.O. Smith GCNH-40, GCNH-50, GNR-40, GNR-50 DATASHEET

Residential Gas Water Heaters

ULTRA-LOW NOx

A. O. Smith Ultra-Low NOx heaters utilize an innovative burner system, a combination of radiant heat and excess air to satisfy Air Quality Management Districts with the requirements of less than 10ng/j for ultra-low NOx emissions.

INTELLIGENT CONTROL LOGIC

The internal microprocessor provides enhanced operating parameters and tighter differentials for precise sensing and fasting heating response to optimize performance.

SELF-POWERED ELECTRONIC GAS VALVE

Uses a Thermopile to generate the power needed to operate the electronics.

DIAGNOSTICS

The electronic gas control incorporates an LED status indicator that monitors system operation & service diagnostics.

FVIR COMPLIANT

Equipped with a flame arrestor that provides smooth ignition and ensures that in the event of accidental exposure to flammable vapors, the vapors are safetly combusted inside the sealed chamber.

DYNACLEAN™ II DIFFUSER DIP TUBE

Helps reduce lime and sediment buildup, maximizes hot water output. Made from long-lasting PEX cross-linked polymer.

COREGARD™ ANODE ROD

A. O. Smith’s exclusive aluminum anode has a stainless steel core, protects tank against corrosion longer versus ordinary steel anodes.

ENHANCED GREEN CHOICE® GAS BURNER

Comprised of inconel alloy and stainless steel ensures long life and exceptional safety.

PUSH-BUTTON PIEZO IGNITOR

Makes lighting pilot fast and easy with one-hand push-button spark ignition.

SIMPLIFIED INSTALLATION

Can be easily installed in the same location as the previous water heater, no special venting or electrical power is required.

DURABLE TAMPER-RESISTANT BRASS DRAIN VALVE

PERMAGLAS

Protects steel tank from corrosion.

CSA CERTIFIED AND ASME RATED T&P RELIEF VALVE

Top-mounted T&P Relief Valve available as option.

CODE COMPLIANCE

UBC, CEC, SBCC, CABO, HUD, BOCA National Codes. Meets the thermal efficiency and standby loss requirements of the U.S. Department of Energy and current edition ASHRAE/IESNA 90.1. Meets the Federal Energy Efficiency Standards effective January 20, 2004, according to the National Appliance Energy Conservation Act (NAECA) of 1992.

DESIGN-CERTIFIED BY CSA INTERNATIONAL

According to ANSI Z21.10.1 - CSA 4.1 Standards governing storage-type water heaters.

6-YEAR LIMITED TANK AND PARTS WARRANTY

For complete information, consult written warranty or A. O. Smith Water Products Company.

Revised December 2010

GLASS COATING

Flame Arrestor

Pilot Assembly/

Combustion Chamber

200 Series Model Shown

Gas Control

View Por

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Residential Gas Water Heaters

ULTRA-LOW NOx

MODEL

NUMBER

TALL MODELS

GCNH-30 8 48-1/2 3 or 4 105

GCNH-40 8 50-3/4 3 or 4 129

GCNH-50 8 49-1/2 3 or 4 151

GNR-40 8850-3/4

GNR-50

Recovery capacity based on actual performance tests. Water Connections – 3/4" on all models. All models may be ordered from the factory with top T&P.

SERIES

200

FIRST

HOUR

RATING

GALLONS

ENERGY FACTOR

50 .61 30 30,000 31 8

65 .59 40 40,000 41 8

75 .58 50 40,000 41 8

70 .62 40 40,000 41 16

75 .62 50 40,000 41 16

GALLON

CAPACITY

BTU

INPUT

PER HOUR

NATURAL

RECOVERY

90ºF RISE

GALLONS

†

PER HOUR

VALUE

DIMENSIONS IN INCHES

A B

59-7/8 56-3/8

62-1/8

60-7/8

61-7/8

60-7/8

58-5/8

57-3/8

58-3/8

57-3/8

OPTIONAL ANODE ROD* LOCATION

HOT CONNECTION

ANODE ROD (OPTIONAL T&P LOCATION)

HOOD

3 or 4

APPROXIMATE

SHIPPING

WEIGHT

(LBS)

DRAFT

E F

OUTLET

49-1/2

COLD CONNECTION

138

160

• Burner system complies with 10ng/j Ultra-low NOx SCAQMD requirements.

• Burner screen acts as a secondary flame arrestor in the event of accidental exposure to flammable vapors.

• If flammable vapors accidentally enter the combustion chamber, the flame trap and burner are designed so flames burn off inside the chamber and cannot escape outside of the heater.

T&P VALVE

1/2" GAS CONNECTION

Maximum Hydrostatic Working Pressure: 150 PSI.

For Technical Information and Automated Fax Service, call 800-527-1953. A. O. Smith Corporation reserves the right to make product changes or improvements without prior notice.

Revised December 2010

www.hotwater.com

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