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Electric Water Heater

Model # MX50255S Official Marathon water heater

Here are the diagrams and repair parts for Official Marathon MX50255S water heater, as well as links to manuals and error code tables, if available.

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For DIY troubleshooting advice and repair guides, visit our repair help section.

Model diagram and schematic

SEARCH WITHIN THIS MODEL

ALL PARTS

Showing 10 of 51 parts |

Temperature And Pressure Relief Valve 330040

Temperature and pressure relief valve

Part #330040

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

Element 610040

Functional replacement parts diagram

Element

Part #610040

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

Dip Tube 230019

Functional replacement parts diagram

Dip tube

Part #230019

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

Protector 310010

Functional replacement parts diagram

Protector

Part #310010

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

Brss Drn Vlv 330090

Functional replacement parts diagram

Brss drn vlv

Part #330090

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

Wrench 610070

#NI

All parts diagram

Wrench

Part #610070

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

Dip Tube 230024

Functional replacement parts diagram

Dip tube

Part #230024

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

Drain Valve 330010

Functional replacement parts diagram

Drain valve

Part #330010

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

Panel 410375

Functional replacement parts diagram

Panel

Part #410375

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

Panel 410969

Functional replacement parts diagram

Panel

Part #410969

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.

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 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 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 making the water too hot?

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

Why is my water heater's pressure relief valve dripping water?

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.…

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