Boss
Gas Water Heater

Model # 5-40-NKRS7 Official Boss gas water heater

Here are the diagrams and repair parts for Official Boss 5-40-NKRS7 gas 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 27 parts  |

Water Heater Thermocouple 9000283
#14

Round gas diagram

Water heater thermocouple

Part #9000283

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

Thermostat 9000246
#9

Round gas diagram

Thermostat

Part #9000246

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

Water Heater Drain Valve 9000254
#19

Round gas diagram

Water heater drain valve

Part #9000254

This item is not returnable
$17.69
10% OFF Phone Price : $19.69
In Stock
Water Heater Manifold Inner Door 9000281
#18

Round gas diagram

Water heater manifold inner door

Part #9000281

$17.69
10% OFF Phone Price : $19.69
In Stock
Rexel Pan Base 9001609
#26A

Round gas diagram

Rexel pan base

Part #9001609

Replaced by #100108616

?
Manufacturer substitution
This part replaces 9001609. Substitute parts can look different from the original.
In Stock
Water Heater Burner 9000390
#16A

Round gas diagram

Water heater burner

Part #9000390

Replaced by #100108399

?
Manufacturer substitution
This part replaces 9000390. Substitute parts can look different from the original.
In Stock
Dip Tube 9001839
#5

Round gas diagram

Dip tube

Part #9001839

Replaced by #100108765

?
Manufacturer substitution
This part replaces 9001839. Substitute parts can look different from the original.
In Stock
Anode Rod 9000705
#6

Round gas diagram

Anode rod

Part #9000705

Replaced by #100300397

?
Manufacturer substitution
This part replaces 9000705. Substitute parts can look different from the original.
$55.38
10% OFF Phone Price : $61.38
In Stock
Pilot 9000284
#15

Round gas diagram

Pilot

Part #9000284

Replaced by #100109070

?
Manufacturer substitution
This part replaces 9000284. Substitute parts can look different from the original.
In Stock
Ring 9000275
#3

Round gas diagram

Ring

Part #9000275

Replaced by #100108369

?
Manufacturer substitution
This part replaces 9000275. Substitute parts can look different from the original.
In Stock

Most common symptoms to help you fix your water heaters

Choose a symptom to see related water heater repairs.

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

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

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

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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