Model # 5-40-1KRT8 Official Thermo-King electric water heater

Here are the diagrams and repair parts for Official Thermo-King 5-40-1KRT8 electric 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 5 of 5 parts |

#20

Round electric diagram

Access bolt

Part #9000928

This item is not returnable

$4.99

In Stock

Qty

#21

Round electric diagram

Access

Part #9000927

This item is not returnable

$4.99

In Stock

Qty

& 322841

Part #N/P

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

Protector

Part #9000726

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

#14

Round electric diagram

Rating plate

Part #0270105

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…

Repair guides for electric water heaters

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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

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

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.

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Model # 5-40-1KRT8 Official Thermo-King electric 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?

Repair guides for electric water heaters

How to replace a water heater element

How to replace an electric water heater anode rod

How to replace an electric water heater thermostat

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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