Model # 8-40-NART7 Official Boss gas water heater

Here are the diagrams and repair parts for Official Boss 8-40-NART7 gas water heater, as well as links to manuals and error code tables, if available.

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Error Codes

Model diagram and schematic

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Showing 10 of 15 parts |

#23

Functional replacement parts diagram

Access bolt

Part #9000928

This item is not returnable

$4.99

In Stock

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#24

Functional replacement parts diagram

Access

Part #9000927

This item is not returnable

$4.99

In Stock

Qty

Functional replacement parts diagram

Box

Part #9000356

This item is not returnable

$4.99

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#22

Functional replacement parts diagram

Access cover

Part #9001764

This item is not returnable

$5.99

In Stock

Qty

Functional replacement parts diagram

Draft hood

Part #9000273

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

#16

Functional replacement parts diagram

Burner

Part #9000288

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

Mnfld w/orfc

Part #9001431

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

#15A

Functional replacement parts diagram

Pilot

Part #9000286

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

#12

Functional replacement parts diagram

Burner

Part #9001627

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

& 322841

Part #N/P

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.

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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 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's pressure relief valve dripping water?

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

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 my water heater making the water too hot?

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

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.

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Model # 8-40-NART7 Official Boss gas 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 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's pressure relief valve dripping water?

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

Why is my water heater making the water too hot?

Effective articles & videos to help repair your water heaters

How to read a wiring schematic video

Easy DIY water heater repairs

Water heater common questions

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