United States
Rheem Rheem
Find a pro
svg-icon
svg-icon
Warranty & Registration Lookup
Register your Rheem product or verify your warranty terms and coverage.
Learn more svg-icon
Find a Pro
Put your water heater and heating and cooling system installation in good hands with a trustworthy, independent Rheem Pro.
Search now svg-icon
Replace a Part
Find what you need to keep your Rheem equipment working perfectly.
Get parts svg-icon
Blogs
Read articles and industry news for homeowners and contractors.
Read more svg-icon
Financing
Don’t let a limited budget keep you from getting the comfort equipment you need for your home or business.
Get financing svg-icon
FAQs
Get answers to all the most frequently asked questions (FAQs) about Heating, Cooling & Water Heating.
Learn more svg-icon
Find Rebates
Search for and find local rebates for your new Rheem heating and cooling solution.
Learn more svg-icon
Project Sizing Solutions
Application Consulting for Customizable Water Heating Solutions.
Get help svg-icon
BIM/CAD Files
Browse and download BIM/CAD files for commercial heating and cooling solutions.
Browse BIM/CAD svg-icon
Financing
Explore financing options to help make your project more affordable.
Get financing svg-icon
Revit files
Browse and download Revit files for commercial water solutions.
Browse Revit svg-icon
Replace a Part
Find what you need to keep your Rheem equipment working perfectly.
Get parts svg-icon
Who We Are
Learn more about Rheem, our history and our commitment to sustainability.
Learn more svg-icon
Sustainability
Learn about our commitment to doing good by our customers, our partners, our employees - and our planet.
Learn more svg-icon
Careers
Passionate, innovative thinkers work here, grow here and impact the next generation. We are driven to provide the perfect degree of comfort for homes and businesses.
Learn more svg-icon
Our Leadership
Find detailed profiles of our company's key executives, highlighting their professional backgrounds, expertise, and roles within the organization.
Learn more svg-icon
News Releases
Stay up to date with the latest news and press releases from Rheem Manufacturing and its family of brands.
Read more svg-icon
Blogs
Read articles and industry news for homeowners and contractors.
Read more svg-icon
svg-icon
Residential Products
svg-icon
United States
Language
Americas
United States United States Canada Canada México México Bolivia Bolivia Brazil Brazil Chile Chile Colombia Colombia Argentina Argentina Perú Perú Ecuador Ecuador Paraguay Paraguay Uruguay Uruguay Honduras Honduras Panamá Panamá El Salvador El Salvador Costa Rica Costa Rica Guatemala Guatemala
Middle East, Asia & Ocenia
Asia Asia Indonesia Indonesia Singapore Singapore Philippines Philippines Vietnam Vietnam Malaysia Malaysia Middle East & Africa Middle East & Africa Australia Australia New Zealand New Zealand
HomeMarathon
INNOVATION
marathon
The Last Water Heater You’ll Ever Need To Buy
Its award-winning construction makes the Rheem® Marathon® water heater the most durable electric water heater ever made. And its industry-best warranty makes it a smart purchase you can count on for years to come.
Unmatched Durability
Our innovative insulation process, seamless liner and tough outer jacket make Marathon the most durable in the business
Simple Installation & Service
Unique design allows one-person installation for fast service, lower costs and quick maintenance
Lightweight Design
Marathon’s lightweight tank is easier to maneuver and position, and features a bowl tank that drains completely
Lifetime Tank Warranty
Tank is built to last for as long as the homeowner owns their home, and backed by a lifetime warranty1

Marathon Point-of-use

Unmatched Durability

15- and 20-Gal. Capacities

Ideal for condos, cabin and light-duty commercial applications

svg-icon

Advanced circuitry ensures that heating elements only turn on when surrounded by water, prolonging their life.

2.5″ polyurethane insulation reduces heat loss for greater energy efficiency.

The Marathon water heater features a seamless, blow-molded plastic inner tank, so it won’t rust or corrode.

Multiple layers of filament wound fiberglass give the tank unmatched strength.
Use & Care
Specification Sheet (U.S.)
Warranty Information

Marathon Standard

Unmatched Durability

30-, 40- and 50-Gal. Capacities

High efficiency design and a lightweight tank that won't corrode

svg-icon

Advanced circuitry ensures that heating elements only turn on when surrounded by water, prolonging their life.

2.5″ polyurethane insulation reduces heat loss for greater energy efficiency.

The Marathon water heater features a seamless, blow-molded plastic inner tank, so it won’t rust or corrode.

Multiple layers of filament wound fiberglass give the tank unmatched strength.
Selling Guide
Specifications Sheet
Submittal
Use and Care Manual

Thermal Storage Tank

Unmatched Durability

50-, 85- and 105-Gal. Capacities

Marathon® thermal storage tanks feature a lifetime limited tank warranty and a 6-year limited parts warranty

svg-icon

Advanced circuitry ensures that heating elements only turn on when surrounded by water, prolonging their life.

2.5″ polyurethane insulation reduces heat loss for greater energy efficiency.

The Marathon water heater features a seamless, blow-molded plastic inner tank, so it won’t rust or corrode.

Multiple layers of filament wound fiberglass give the tank unmatched strength.

Brochure (US and Canada)
Marathon & KwikComfort Deliver a Legacy of Savings
Residential KwikComfort® Financing makes it easy and smart to enjoy hot water that lasts a lifetime. With low monthly payments, your Marathon Water Heater will only make a small impact on your monthly budget. And because it’s built to last, your Marathon will still be going strong long after it’s paid off.

Nothing Compares to Marathon Water Heaters

Marathon Plastic Tank
Competitor stainless steel tank
Number of Replacement Units Allowed
Perpetual
1 Per Customer
Warranty Unrestricted by Water Conditions
Warranty Unrestricted by Water Temperature
Warranty Transferable
Low Product Weight
Dry Fire Protection
Element
Titanium
Stainless Steel
Dent / Corrosion Resistant Jacket
Saltwater-Resistant Jacket
svg-icon
Download Brochure
svg-icon
svg-icon
Specification Sheets
svg-icon
svg-icon
Use & Care Manual
svg-icon
Get a Rheem Marathon Water Heater Today
Ready to enjoy a lifetime of hot water?
Helpful for Homeowner
Water Heaters
Heating & Cooling
Home Innovations
Pool & Spa Heaters
EcoNet®
ENERGY STAR® Products
Commercial Solutions
Commercial Water Heaters
Heating & Cooling
Commercial Innovations
Builders Program
Commercial Financing
Professionals
MyRheem Portal
Become a Rheem Pro
Replace a Part
Contractor Financing
Training
About Rheem
Who We Are
Sustainability
Careers
Blogs
Global Locations
Help & Support
Tools & Resources
Find a Pro
Product Registration
Water Heating Blog
Air Conditioning Blog
Rebate Center
Federal Tax Credits
Homeowner Financing
Frequently Asked Questions
HVAC KnowZone
Water Heating Technical Bulletins
Commercial Water Cross Reference Tool
Rheem Social
X YouTube LinkedIn Facebook Instagram
Rheem Mobile
googlePlay appStore
Find a Pro by City
See All
Atlanta, Georgia
Austin, Texas
Boston, Massachusetts
Charlotte, North Carolina
Chicago, Illinois
Houston, Texas
Dallas, Texas
Denver, Colorado
Detroit, Michigan
El Paso, Texas
Fort Worth, Texas
Indianapolis, Indiana
Jacksonville, Florida
Los Angeles, California
Memphis, Tennessee
Nashville, Tennessee
New York, New York
Oklahoma City, Oklahoma
Philadelphia, Pennsylvania
Phoenix, Arizona
Portland, Oregon
San Antonio, Texas
San Diego, California
San Francisco, California
San Jose, California
Seattle, Washington
Copyright 2004–2025 Rheem Manufacturing Company. All Rights Reserved.
Privacy Notice Website Terms & Conditions Supplier Code of Conduct Cookie Policy ADA Accessibility Guidelines