Marathon Water Heaters

Marathon water heaters are unique and very simple electric heating appliances with the three great features; lifetime warranty on the water tank, high efficient operation and easy installation.

Features and Advantages

One of the main advantages, or if I can say the best features we can see on the Rheem Marathon electric water heaters is Marathon's lifetime warranty on its tanks. This means that you don't have to buy a heater every 10 years or so, due to the rust problems and tank leaking. With such a design, less garbage goes into the landfills.

Marathon hot water heater tank is made of the seamless blow molded polybutene patented as the PermaGuard, and such a tank design eliminates the need for the anode rod, a component part used for corrosion protection. With the absence of the anode rod, smelly water problem, or rotten egg smell is eliminated.

Marathon heater tank is insulated with the 2.5" thick Envirofoam insulation with the high insulation value of R 20. 4' pipe insulation is included in the package so together with the good tank insulation they can work together to provide higher energy efficiency values and reduce the energy loss. Due to its superb insulated tank design Marathon manufacturer claims that there is only 5 F of heat loss in 24h.

Outer tough molded tank on Marathon water heaters is made of the polyethylene with the multiple layers of filament wound fiberglass to increase the durability to the unit so it can withstand higher hot water pressure, when compares to the standard heaters, making it resistant to the dents and scratches.

Dip tube is the commercial grade with the unique design, to provide the turbulence in the incoming cold water and at the bottom of the tank, in order to reduce the sediment build-up. Bowl shaped bottom of the tank allows easier draining.

Standard Marathon water heaters are equipped with the two stainless steel heating elements, low watt-density coated elements for greater performance, durability and efficiency. Thermally fused upper element provides protection against "dry-firing" and stainless steel incoloy lower element provides protection against the lime build-up.

T&P relief valve and vacuum relief valve are factory installed, and like other plumbing connection Marathon heaters are using standard 3/4" size.

All the Marathon component parts have the limited warranty of 6 years.

Also, light weight construction means inexpensive, easy and safe installation.

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As said before, you can find three groups of Rheem Marathon water heaters; for residential, commercial and point of use applications.

There are ten models in total available with the smallest MR15120, 15-gallon point of use heater, which has only one heating element, to the largest MR105245, 105-gallon tank size whose first our rating has the maximum 104 gph.

All of the Marathon models are designed with the very high energy factor (due to the features described above), which is from 0.9 to 0.94 (found only on 30, 40 and 50-gallon models).

Residential models are built in the most popular sizes, 40, 50, 85 and 105-gallon size (recommended for families with 4 to 7 members), tall in height, while 50-gallon unit can be found as tall and short also.

Maximum heating power is 4500 kw on the heating elements, which uses 240 V, while the minimum is 2000 kw which is using 120 V.

Marathon point of use water heaters are design for space-saving and installation in limited spaces. They are using the same quality and features as the larger heaters, but due to its small size, they are used for point of service applications, usually installed under the sink, lavatories, apartments, condos, camps and restrooms in offices.

Three models, two sizes, 15 and 20-gallon to choose from, residential point of use Marathon water heaters come with the lifetime warranty for the tank and 6 years on parts, and if used for light duty commercial applications, warranty for tanks changes to 10 years and for parts only one.

Marathon heavy duty electric water heaters are designed for installation in harsh environments and for high temperature applications as they can heat the water up to 175 F.

There are two heavy duty Marathon hot water heaters, 85 and 105-gallon, both tall in size. They are also providing superior design with the upgraded titanium sheath elements, used for the extreme water conditions.

If you are planning to use an alternative energy source, like solar water heating or geothermal, or in combination with the hydronic system than Marathon "Multi-Port" thermal storage tank is the ideal solution for you. You can choose between three models, standard sizes of 50 gallons, 85 and large 105 tank size.

Heavy duty Marathon water heaters are equipped with the thick insulation to reduce the heat loss even more. The multiport design utilizes the large water connections, conveniently located in front of the unit, and for backup heating, electric heating elements.

Either you are buying a full size, standard height water heater, heavy duty or point of use, you will not go wrong with Marathon electric water heaters. Rheem Marathon is an expensive water heater, the price for the 50-gallon heater, Rheem MSR50245 is over $1000 (found on the Amazon online store), but it provides two awesome features; lifetime warranty and high energy efficiency factor.

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