Model # GPDX75100 Official AO Smith water heater

Here are the diagrams and repair parts for Official AO Smith GPDX75100 water heater, as well as links to manuals and error code tables, if available.

There are a couple of ways to find the part or diagram you need:

Click a diagram to see the parts shown on that diagram.
In the search box below, enter all or part of the part number or the part’s name.

Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.

We encourage you to save the model to your profile, so it’s easy to access parts and manuals for your appliance whenever you log in.

For DIY troubleshooting advice and repair guides, visit our repair help section.

Error Codes

Model diagram and schematic

SEARCH WITHIN THIS MODEL

ALL PARTS

Showing 10 of 46 parts |

#13

Water heater diagram

Dip tube

Part #183900-028

Replaced by #9003667005

$8.49

In Stock

Qty

#NI

Water heater diagram

Nipple

Part #184633-002

Replaced by #100108409

$25.71

In Stock

Qty

#13A

Water heater diagram

Inlet tube

Part #183901-040

Replaced by #9002432005

$26.99

In Stock

Qty

#12

Water heater diagram

Temperature valve

Part #043151-000

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

#14

Water heater diagram

Anode rod

Part #183523-039

Replaced by #100109594

$55.56

In Stock

Qty

#19

Water heater diagram

Burner

Part #194549-000

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

Water heater diagram

Adapter

Part #181557-000

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

#NI

Water heater diagram

Anode

Part #184977-216

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

#18C

Water heater diagram

Orifice

Part #181791-044

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

#15

Water heater diagram

Wiring harness

Part #184289-000

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

Most common symptoms to help you fix your water heaters

Choose a symptom to see related water heater repairs.

View all

Why isn't my water heater heating my water?

Main causes: lack of power, no gas supply, thermostat limit switch tripped, bad element, bad thermostat, gas valve failu…

Why isn't my water heater making the water hot enough?

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

Why is there water in my water heater's drain pan?

Main causes: loose water pipe fittings, leaky drain valve, bad temperature-pressure relief valve, leaky heating element,…

Why does my hot water smell like rotten eggs?

Main causes: water supply needs chlorine treatment, anode rod too reactive…

Why isn't my water heater making enough hot water?

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

Why is my water heater making the water too hot?

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

Why is my water heater's pressure relief valve dripping water?

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

Effective articles & videos to help repair your water heaters

Use the advice and tips in these articles and videos to get the most out of your water heater.

View all

Wiring schematic symbols explained video

Model # GPDX75100 Official AO Smith water heater

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Most common symptoms to help you fix your water heaters

Why isn't my water heater heating my water?

Why isn't my water heater making the water hot enough?

Why is there water in my water heater's drain pan?

Why does my hot water smell like rotten eggs?

Why isn't my water heater making enough hot water?

Why is my water heater making the water too hot?

Why is my water heater's pressure relief valve dripping water?

Effective articles & videos to help repair your water heaters

Wiring schematic symbols explained video

Using a wiring schematic to trace a current video

Easy DIY water heater repairs

Parts & More

Stay Connected

Quick links

Let us help you

More resources