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Electric tank water heater?

Myrtleboone | Posted in General Questions on

Hi. I am back and forth about purchasing either the Rheem Marathon or your run-of-the-mill steel tank electric hot water heater. I have read that the Marathon series is no more efficient than a standard tank (EF factor), however, has the advantage of not rusting out. So what’s the advantage of all that foam on the Marathon? It costs 2/3+ more and its tank is made out of polybutylene which is a bit worrisome. Any recommendations on kind, as well as sizing (2 adults, 2 kids; are fairly water conservation minded); I’m thinking an 50-75 gallon would work? With all that said, should I consider tankless?
Thanks in advance. Matt

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  1. wjrobinson | | #1

    Better and bigger vs not better and not bigger. You answered your own questions.

    Steel lowest cost.
    Stainless steel highest cost.
    Heat pump another option.
    Marathon another option. Don't like plastic, easy, drop from choices.

    Steel tanks, may last longer if anode is replaced periodically.

    Small tanks limit water use which lowers utility costs. Big tanks are a luxury many desire and pay more for.

    It's pretty simple. Decide what you value.

  2. davidmeiland | | #2

    Marathon has (had?) a lifetime warranty to the original owner, and while the tank won't rust out I have heard of leaks. I would rarely recommend one. You should be good with a 50-gallon tank. If you live in a hot climate a heat pump water heater might perform well. Check the rebates and incentives--for a while they were net cheaper here than standard units.

  3. GBA Editor
    Martin Holladay | | #3

    You are correct that the Marathon is no more efficient than other brands. All electric-resistance water heaters are 100% efficient at heating water; the only difference is the thickness and quality of the insulation. (Marathon insulation is good.)

    The main disadvantage of tankless electric heaters is that they require 200-amp electrical service and expensive wiring costs. Talk to an electrician before installing one or more of these heaters.

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