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  1. Electric, Natural Gas or Propane?
    Of all the fuels available, electric water heaters will have the highest energy efficiency. Your local energy costs though may make cost of operation less for one than another even if it is less efficient. Generally speaking, a Marathon will be less expensive to operate than propane in nearly all markets and due to the volatile nature of natural gas prices, Marathon is now the least cost alternative compared to natural gas in many markets.

  2. How do I know how efficient a tank is?
    The best judge is Energy Factor (EF) which is a mandatory evaluation done on all water heaters. It takes into account usage, standby loss, insulation, etc all under simulated actual conditions. In all categories, we will have one of the highest EF of any tank on the market. This means the Marathon is only heating the water you use.

  3. What do I look for in a water heater warranty?
    First, check the length of the warranty. According to DOE the average life expectancy of a water heater is no more than 10 years. If your last heater lasted 20 years, be thankful. Remember, installation costs are the same for most electric heaters and who wants to pay that every time a water heater is replaced? Also consider the damage that can occur if your heater leaks and you don't catch it right away. Marathon offers the purchaser a lifetime "no-leak" warranty (in residential applications). If your tank leaks in normal applications, we give you another — that's it, no strings, double talk or pro-rating of your tank. Isn't that the way it should be?

  4. What else do I look for on the tank?
    What is included on the tank? Marathon INCLUDES a factory installed temperature and pressure (T&P) relief valve, union fittings for all connections, a vacuum relief valve, and 4' of pipe insulation. Look for quality components too. We use brass drain valves and fittings. Our tank is actually "bowl shaped" at the bottom to allow for more complete sediment removal and draining.

  5. What size do I need?
    How many people do you have in your family? Any other large hot water uses in your home such as whirlpools or Jacuzzis? Although there may only be two in the home now, if it is a 4 bedroom home we recommend sizing it for the potential use as it will help potential resale. Remember, you are buying a lifetime heater with low operating cost.

Number in Family: 1-2 3-4 5-6(or water heater under control) >6
Tank Size: 30, 40, or 50 50 or 85 85 105

* We recommend a minimum of an 85 gallon or larger for whirlpools and Jacuzzis