Marathon
Electric Water Heater

Model # MX85255 Official Marathon water heater

Here are the diagrams and repair parts for Official Marathon MX85255 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 51 parts  |

Control 310020
#6B

Functional replacement parts diagram

Control

Part #310020

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

Dip Tube 230019
#16H

Functional replacement parts diagram

Dip tube

Part #230019

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

Drain Valve 330010
#2

Functional replacement parts diagram

Drain valve

Part #330010

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

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
#3

Functional replacement parts diagram

Element

Part #610040

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

Protector 310010
#5B

Functional replacement parts diagram

Protector

Part #310010

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

Control 310030
#12

Functional replacement parts diagram

Control

Part #310030

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

Panel 410969
#9GB

Functional replacement parts diagram

Panel

Part #410969

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

Dip Tube 230025
#16G

Functional replacement parts diagram

Dip tube

Part #230025

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: 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.…