Rheem Marathon electric water heater

Possibly the last water heater you’ll ever need to buy

If you’re looking for a reliable, durable, and energy-efficient water heater for your homestead, off-grid, or self-reliant lifestyle, you might want to consider the Rheem Marathon Electric water heater. In this post, we will share with you why we love this water heater and how it has made life easier and more comfortable.

The Rheem Marathon Electric water heater is a tank-type water heater that uses electricity to heat water. Heating water is not a cheap nor an energy efficient thing to do. As such, we have seen an advent in things that are anti-tank water heaters, but there are multiple downsides to “instant hot water” or tankless water heaters, especially for those trying to live off-grid.

The Marathon tank comes in various sizes and capacities, but the one we have is the 40 gallon (181.84 l) model that runs on 3 kilowatts of power. This is fairly low for an electric water heater, which means it does not consume too much electricity and can be powered by a solar system or a generator with some work. Don’t forget as well, a tank of hot water is also a backup tank of hopefully drinkable water, and that a tank water heater in general is a fancy thermal battery. While the 3KW version has done as well, in another life or a new design we will likely be using the smaller, point of use 120V, 20 gallon (90.92 l) 2KW variations and run more than one.

Well that’s nice and a lot of text, but can we actually get to something of substance here? Sure. We bought this to replace a 23-year-old 3KW, 240V, 40 gallon (181.84 l) electric water tank. The benefit off the bat, what that we did not need to re-wire anything, however we had an old fuse switch that we also swapped out.

Why not grab one of those fancy new heat pump water heaters, like the ProTerra? The ProTerra is estimated to cost less than $200 CDN to heat water for the year if you only run the heat pump. This seems great since the marathon is estimated to be around $400, and it’s way easier to provide power in 120V, will require less panels, etc. Well, yes. That’s true, and it’s a decent unit and likely great in the burbs, but there’s a number of additional factors that the average consumer may not consider, and we’re not an average consumer are we? Well, those still have a regular glass-lined tank and an anode rod which isn’t very easy to get with a heat pump thrown to the top of your water tank.

The marathon water tank is the ultimate sustainable (in terms of throwing out the whole product vs not) and off-grid/homesteader product since the tank is a newer blow-molded plastic inner tank (we use pex now anyway, so difference?) with 2.5″ of polyurethane insulation which in essence turns this thing into a big “bubba” or similar thermos-style tech. This means that the tank won’t rust out, there’s no anode rode, comes with dry fire protection, and in reality is about 5 parts total that may need replacing, that you can 100% do yourself and we have. If you have the parts, this could last you the rest of your life.

The best part is that this water heater only has six parts that need to be replaced over time: the heating elements, the thermostats, the relief valve, and the drain valve. These parts are easy to find and replace, and they do not cost much. Compared to other water heaters that have many more parts that can break down or wear out, the Rheem Marathon Electric water heater is a breeze to maintain and repair. The simple fact that the marathon tank is calcium/river friendly means it plays nice on well systems and for $5,000 in additional parts you could have a potential lifetime stockpile of things to keep the tank going. Something that cannot be said for anything else on the market, including tankless water heaters (electric or gas).

It’s also worth mentioning that it has a bowl-shaped tank bottom that drains completely, making it easy to clean and maintain and comes with a manual that’s actually useful and made setup a breeze. It makes maintenance just as easy with everything required printed and ready for you.

This water heater is perfect for homesteaders, off-gridders, and self-reliant people who want to have hot water without worrying about leaks, repairs, or replacements. It is also good for the environment because it reduces waste and energy consumption. We have been using this water heater for over a year now and have not had any issues with it. It provides us with enough hot water for our daily needs, and it keeps our electricity bill relatively low.

If you are interested in getting this water heater for yourself, we got ours at Home Depot and all spare parts from parts.rheem.com.

The Rheem Marathon Electric water heater is one of the best investments we have made for our homestead. It has saved us money, time, and hassle. It has also improved our quality of life by providing us with hot water whenever it’s needed. After about 45 minutes, we have enough to shower from a fresh installation.