Boss
Water Heater

Model # 5-40-20RT8-2 Official Boss electric water heater

Here are the diagrams and repair parts for Official Boss 5-40-20RT8-2 electric 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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ALL PARTS
Showing 10 of 23 parts  |

Thermostat 9000510
#7

Round electric diagram

Thermostat

Part #9000510

Replaced by #9001954015

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Manufacturer substitution
This part replaces 9000510. Substitute parts can look different from the original.
BEST SELLER
$28.93
17% OFF Phone Price : $34.93
Back Order
Water Heater Heating Element Gasket 9000308
#4

Round electric diagram

Water heater heating element gasket

Part #9000308

Replaced by #9000308005

?
Manufacturer substitution
This part replaces 9000308. Substitute parts can look different from the original.
$30.62
16% OFF Phone Price : $36.62
In Stock
Anode Rod 9000705
#2

Round electric 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
Access Bolt 9000928
#20

Round electric diagram

Access bolt

Part #9000928

This item is not returnable
In Stock
Access Cover 9001764
#19

Round electric diagram

Access cover

Part #9001764

This item is not returnable
In Stock
Access 9000927
#21

Round electric diagram

Access

Part #9000927

This item is not returnable
In Stock
Water Heater Thermostat Bracket (replaces 0110238, 0110238-01, 0110322, 9000309015) 9000309
#12

Round electric diagram

Water heater thermostat bracket (replaces 0110238, 0110238-01, 0110322, 9000309015)

Part #9000309

Replaced by #100108380

?
Manufacturer substitution
This part replaces 9000309. Substitute parts can look different from the original.
In Stock
Anode Rod 9001828
#15

Round electric diagram

Anode rod

Part #9001828

Replaced by #100109594

?
Manufacturer substitution
This part replaces 9001828. Substitute parts can look different from the original.
In Stock
Drip Pan 9000741
#23

Round electric diagram

Drip pan

Part #9000741

Replaced by #9002846

?
Manufacturer substitution
This part replaces 9000741. Substitute parts can look different from the original.
In Stock
Drain Pan 9000743
#23B

Round electric diagram

Drain pan

Part #9000743

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.

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

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

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

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

Repair guides for electric water heaters

How to replace a water heater element

How to replace a water heater element

If your water heater runs out of hot water quickly and one of the two heating elements has failed, replace the element f…

Repair difficulty
Time required
 30 minutes or less
How to replace an electric water heater thermostat

How to replace an electric water heater thermostat

If the water temperature fluctuates or you don't get enough hot water, follow these instructions to replace your water h…

Repair difficulty
Time required
 30 minutes or less
How to replace a water heater temperature and pressure (T&P) relief valve

How to replace a water heater temperature and pressure (T&P) relief valve

Replace a broken temperature/pressure (T&P) relief valve on an electric water heater using these instructions.…

Repair difficulty
Time required
 15 minutes or less

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.

Wiring schematic symbols explained video

Wiring schematic symbols explained video

Learn some of the most common symbols found in a wiring diagram and what they mean.…

Using a wiring schematic to trace a current video

Using a wiring schematic to trace a current video

Find out what’s wrong with your appliance by following a circuit.…

Easy DIY water heater repairs

Easy DIY water heater repairs

Read about some water heater repairs that you can easily do yourself.…