AO Smith
Gas Water Heater

Model # GNR40100 Official AO Smith water heater

Here are the diagrams and repair parts for Official AO Smith GNR40100 water heater, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 19 parts  |

Water Heater Manifold Door Gasket 9006141015
#15

Water heater diagram

Water heater manifold door gasket

Part #9006141015

This item is not returnable
$25.49
19% OFF Phone Price : $31.49
In Stock
Ao Smith Flue Baffle 9006436005
#3

Water heater diagram

Ao smith flue baffle

Part #9006436005

In Stock
Ring 700795-021
#2

Water heater diagram

Ring

Part #700795-021

In Stock
Temperature Valve 9000728015
#8

Water heater diagram

Temperature valve

Part #9000728015

The manufacturer no longer makes this part, and there's no substitute part

Ao Smith Water Heater Burner Assembly 9006443005
#13

Water heater diagram

Ao smith water heater burner assembly

Part #9006443005

Replaced by #100093859

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Manufacturer substitution
This part replaces 9006443005. Substitute parts can look different from the original.
In Stock
Control Valve 9006440005
#10

Water heater diagram

Control valve

Part #9006440005

Replaced by #100093863

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Manufacturer substitution
This part replaces 9006440005. Substitute parts can look different from the original.
In Stock
Dip Tube 9006431005
#6

Water heater diagram

Dip tube

Part #9006431005

Replaced by #100111192

?
Manufacturer substitution
This part replaces 9006431005. Substitute parts can look different from the original.
In Stock
Connector 9006449015
#14

Water heater diagram

Connector

Part #9006449015

Replaced by #100093865

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Manufacturer substitution
This part replaces 9006449015. Substitute parts can look different from the original.
In Stock
View Port 9006142015
#16

Water heater diagram

View port

Part #9006142015

Replaced by #9006142015

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Manufacturer substitution
This part replaces 9006142015. Substitute parts can look different from the original.
In Stock
Drafthood 700795-020
#1

Water heater diagram

Drafthood

Part #700795-020

Replaced by #100111362

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Manufacturer substitution
This part replaces 700795-020. Substitute parts can look different from the original.
In Stock

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Main causes: broken heating element, thermostat failure, excessive tank sediment, tank size too small, burner valve asse…

Main causes: faulty pressure relief valve, water is overheating…

Main causes: thermostats need adjustment, water heater capacity too low, bad heating element, thermostat failure, excess…

Main causes: thermostat temperature set too high, thermostats need adjustment, faulty thermostat, shorted heating elemen…

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