Rheem® Marathon® Heaters

Beginning December 2023, Mountain Air And Heat will be providing installation and service for the Marathon Heater series of water heaters by Rheem. The Marathon Heater tank uses new specialized technology to provide advantages in water heating service and durability that have rarely, if ever, existed in residential water heating units before. Available in 15-20 gallon units, 30-50 gallon units and 50-105 gallon units, the Marathon Heaters use a polybutene/plastic composite jacket and titanium to provide a low-weight tank that is protected against dry fires, resistant against dents and corrosion and resistant against saltwater. The 2.5″ polyurethane insulation design also provides better protection against heat loss and will raise energy efficiency in your home.

From here, we’re going to provide additional details that come from Rheem themselves as part of the information sent to us as a service technician for the Marathon Heater. Take a look below:


Marathon Water Heater – The Best

Best Construction
No rust, no corrosion – ever! Unique 2-ply PermaGuard design, a seamless, blow-molded polybutene inner tank wrapped in filament-wound fiberglass. Great for brutal well water conditions.

Best Durability
Toughest and strongest tank in the residential water heater industry. No one comes close. Marathon tanks are regularly tested to withstand 100,000 cycles from zero-to-150 psi. Even ‘high-end’ steel water heaters struggle to make it 1/4th the way through this punishment.

Best Functionality
Beauty more than skin deep. No anode rod means no rotten-egg smell from sulfates found in many water systems. Easy-on/easy-off water connections. Self-cleaning action of bowl shaped tank bottom, coupled with a brass drain valve at the very bottom of the tank provides for more complete draining.

High Efficiency
Save on your energy bill. 2.5 inches of Envirofoam® insulation minimizes stand-by heat loss. No ‘heat-trap’ fittings that can clog or chatter.

Best Value
Marathon’s renowned durability eliminates the cost of buying and the cost of re-installing a new water heater every 10-years (national average). This coupled with energy savings makes the total cost of ownership lower than typical water heaters.

Best Warranty
Lifetime tank warranty – the last water heat you will need to buy for your home. If tank fails, you get a new Marathon with no “pro-rating” deductions. Selling your home, making a warranty claim, use in multi-family, commercial/industrial/agricultural or high-temperature applications does not void warranty.

“Green Power” Ready
Ready to use for ‘thermal storage’ with go-thermal heat pumps, solar and Green/Renewable Energy Conduit between control boxes facilitates wiring for ‘Oil-Peak’ and special controls.

We encourage you to see more about the Rheem Marathon Heater and additional graphs (for which the images above came from) on their official product page at https://www.rheem.com/innovations/innovation_residential/marathon/.