Marathon Water Heater – Energy Savings

How do we measure the efficiency of hot water heaters? Why is a Marathon water heater more efficient that an electric water heater or gas water heater?

The efficiency of water heaters is measured by its Energy Factor (EF). A higher energy factor means that a water heater is more efficient and costs less to operate. Most water heaters available in the United States have an energy factor between 0.48 – 0.70 EF (gas water heaters) and 0.78 -0.94 EF for (electric water heaters). Marathon water heaters have an energy factor of up to 0.94 EF. A Marathon water heater is not just super energy efficient, but also the most durable and best electric water heater on the market today.


What makes a Marathon water heater more efficient than an electric water heater?

Marathon water heaters have electric water heater elements that are submerged in the water  stored in the tank. The electric water heater elements transfer close to 100% of the electric resistant heat from the heating elements to the water. The efficient transfer of  heat by Rheem Marathon water heaters ensures that there are few if any energy efficiency losses. Marathon water heaters are built to maximize the availability of efficiently generated hot water.

Secondly, Marathon water heaters are super-insulated with envirofoam. An old electric water heater often has an energy factor of 0.78 EF. It needs to use almost 20% more energy just to keep the water warm due to poor insulation of the water heater and associated standby losses. These old water heaters were often retrofitted with water heater blankets to reduce heat losses. Marathon water heaters by Rheem have minimized standby losses by super-insulating the electric water heater tank.

Marathon water heaters keep your water hot. It is not unheard of for people to have an ongoing supply of hot water lasting several days through a power outage. When experiencing  a loss of power, Marathon water heaters lose  as little as 5% of the heat stored in the tank per 24 hour period. We know of people in the Midwest that take a 20 gallon Marathon water heater with preheated hot water on their hunting trips to ensure access to a reliable supply of hot water throughout a hunting weekend spent in the woods.


What makes a Marathon water heater more efficient than gas water heaters?

Compared to an electric Marathon water heater, gas water heaters operate by burning gas in a combustion chamber. The hot exhaust gases are routed though a flue that is situated directly in the center of the water heater.

On its way up through the flue the hot exhaust gases are transferring the heat to the water stored in the gas water heater. The problem is that a lot of heat goes up through the flue, a duct, and out the chimney instead of getting transferred to the water. Gas water heaters are very inefficient when it comes to transferring heat from the exhaust to the water. A lot of heat stays in the exhaust instead of getting transferred to the water stored in the tank.

Natural draft gas water heaters rely on the exhaust from the water heater to be hot. Hot exhaust travels through the flue and duct by a process referred to as convection, which essentially states that heat rises. The exhaust gases in a natural draft gas water heater need to be hot to properly vent the toxic exhaust gases to the exterior of the home. Unfortunately, home owners with a natural draft gas water heater are not just paying to heat water, but are also paying for precious heat that is left in the exhaust.

When a gas water heater is not actively heating water, the flue in the center  can become a main source of problems. The open flue allows for cold air to move directly through the center of the water heater.  Since the water heater flue is not insulated it causes the hot water stored in the tank to rapidly cool down requiring additional gas consumption for the water to stay hot overtime.

Compared to a gas water heater Marathon water heaters are heavily insulated to prevent the water from being cooled down by the ambient air and do not generate toxic exhaust gases that need to be routed through an inefficient flue and exhaust duct. The water heating elements are submerged in the water stored in the tank allowing for efficient heat transfer.

Rheem, the manufacturer of Marathon water heaters, also recommends adding pipe wrap insulation to the first six feet of hot water pipe that is connected to the Marathon heater. This reduces unnecessary standby losses.


How can I make my home carbon neutral with a Marathon water heater? How is it possible to eliminate green house gases by choosing a Marathon water heater?

Highly efficient modern home builders often choose to build  all electric homes. Advanced homes built to ENERGY STAR specifications, such as the Passivhaus design or net zero homes, often include all electric appliances throughout the home. All electric homes do not use natural gas, propane, oil, diesel, biodiesel, or any other carbon containing fuel to heat the air or water in a home.

Home owners wanting to reduce their carbon footprint will often choose a Marathon water heater and sign up for their electric utility’s renewable power program. Many utilities offer renewable power programs which supply home owners with 100% power generated by wind, solar, or water. Choosing a renewable power program and installing a Marathon water heater can contribute greatly towards reducing a homeowner’s carbon footprint..

Alternatively, home owners can use a Marathon water heater as a stepping stone toward carbon neutral living by installing an add-on solar hot water heater system or a solar photovoltaic system at their home at a later point. A solar thermal system can reduce the energy use of a Marathon water heater by up to 50%. Solar photovoltaic arrays can supply 100% of the energy used by a Marathon water heater eliminating the need to burn any fossil fuel to heat water for the home.


Why do Home Performance Contractors often replace an existing gas water heater with a Marathon water heater?

Home Performance contractors and weatherization contractors are highly trained and qualified energy experts. They specialize in diagnosing air leaks, proper levels of air exchanges, and unsafe conditions in your home. Anecdotal evidence from weatherization contractors suggests that one in five homes tested for energy efficiency and safety has a gas appliance that is not properly vented. These gas appliances can cause toxic exhaust gases to unnecessarily stay in the home reducing indoor air quality.

Natural gas or propane water heaters can release carbon monoxide, NOX, and other pollutants which need to be vented. Many weatherization contractors eliminate this issue entirely by installing the energy-efficient Marathon water heater.

Choosing a Marathon water heater enables home owners to create a healthy living environment due to the water heater’s high quality features including good insulation, outstanding efficiency, and maintenance of great indoor air quality. Marathon water heaters make it possible for your home to become more energy efficient.

Marathon water heaters are available just about anywhere in the United States of America. A Marathon water heater can be installed as a DIY project or by a qualified contractor. Marathon water heaters are available in a variety of sizes for residential and commercial use. Explore the full line of Marathon water heaters. If you are ready to replace your existing water heater with a Marathon water heater, visit our list of factory authorized contractors, retailers, and wholesalers.