Thermo-King
Water Heater

Model # 5-40-20LS8 Official Thermo-King electric water heater

Here are the diagrams and repair parts for Official Thermo-King 5-40-20LS8 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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Showing 10 of 17 parts  |

Thermostat 9000510
#16

Functional replacement parts 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.
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$28.93
17% OFF Phone Price : $34.93
In Stock
Water Heater Heating Element Gasket 9000308
#4

Functional replacement parts diagram

Water heater heating element gasket

Part #9000308

Replaced by #9000308005

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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

Functional replacement parts 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
Water Heater Thermostat Bracket (replaces 0110238, 0110238-01, 0110322, 9000309015) 9000309
#8

Functional replacement parts diagram

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

Part #9000309

Replaced by #100108380

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Manufacturer substitution
This part replaces 9000309. Substitute parts can look different from the original.
In Stock
Dip Tube 9001823
#12

Functional replacement parts diagram

Dip tube

Part #9001823

Replaced by #100108611

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Manufacturer substitution
This part replaces 9001823. Substitute parts can look different from the original.
In Stock
Drain 9000058
#9

Functional replacement parts diagram

Drain

Part #9000058

Replaced by #100108269

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Manufacturer substitution
This part replaces 9000058. Substitute parts can look different from the original.
In Stock
Drain Pan 9000743
#13B

Functional replacement parts diagram

Drain pan

Part #9000743

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

Thermostat 9000507
#15

Functional replacement parts diagram

Thermostat

Part #9000507

Replaced by #9000507015

?
Manufacturer substitution
This part replaces 9000507. Substitute parts can look different from the original.
$33.17
15% OFF Phone Price : $39.17
In Stock
Wheelers Water Heater Temperature And Pressure Relief Valve 9000728
#1

Functional replacement parts diagram

Wheelers water heater temperature and pressure relief valve

Part #9000728

Replaced by #100108455

?
Manufacturer substitution
This part replaces 9000728. Substitute parts can look different from the original.
In Stock
Thermostat 9000509
#7

Functional replacement parts diagram

Thermostat

Part #9000509

Replaced by #100108424

?
Manufacturer substitution
This part replaces 9000509. 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…

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 anode rod

How to replace an electric water heater anode rod

If your hot water begins to smell like rotten eggs, replace the anode rod with a zinc-aluminum anode rod following the i…

Repair difficulty
Time required
 15 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

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.

How to read a wiring schematic video

How to read a wiring schematic video

Learn how to decipher symbols so you can buy the right part for your problem.…

Easy DIY water heater repairs

Easy DIY water heater repairs

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

Water heater common questions

Water heater common questions

These common questions and answers can help you make the most of your water heater.…