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Community and Q&A

Is it cost-effective to get a lifetime hot water tank?

lmpifer | Posted in Energy Efficiency and Durability on

I have a gas hot water tank now, and understand that lifetime tanks are electric, which means I’d have to convert from gas to electric. I’m wondering if it’s a wise choice, since electricity is
so much more expensive than gas. My current hot water heater is about 11 years old.

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  1. davidmeiland | | #1

    What rates do you pay for gas and electricity?

    The Rheem "Marathon" is an electric tank with a lifetime warranty to the original owner (last time I checked). The big advantage I see is the possibly somewhat lower likelihood of a tank leak. Typical tanks always rust out, eventually.

  2. PAUL KUENN | | #2

    Go Solar!

    This week with -20F and some sun we didn't need any power to heat our water. In fact 70% of the year it's taken care of by the sun. Marathons are nice and you can easily fit an external heat exchanger to the electric ports. You can use a small backup air heat pump to heat water on the sunless stretches (electrically more efficient).

    I'd choose air heat collectors vs liquid. Liquid thermal collectors (mostly Copper) are more efficient but now very pricey. Two hot air collectors and an air to water exchanger is less problematic and less expensive.

  3. GBA Editor
    Martin Holladay | | #3

    Assuming that you have access to natural gas (rather than propane), then it will be almost certainly cheaper to stick with a gas water heater. It isn't very unusual for a gas water heater to last only 11 or 12 years.

  4. GBA Editor
    Martin Holladay | | #4

    First of all, solar thermal equipment is so expensive that it is almost impossible for a solar thermal system to be cost effective compared to natural gas. Moreover, even if you want to invest in solar energy, PV usually makes more sense than solar thermal equipment. For more information, see Solar Thermal is Dead.

    Finally, I'm confused by your suggestion that it makes sense to install "[solar] air heat collectors vs. liquid [collectors]" and that it is a good idea to connect "two hot air collectors" to "an air to water exchanger."

    You are the only person on the planet who thinks that this Rube Goldberg device would be efficient or cost-effective.

  5. user-1061844 | | #5

    if you swap out the sacrificial anode in time (ie before it is completely corroded) - your gas or electric hot water tank should be able to last you a lifetime.

    this is also the main difference in a tank between a 6-, 8- or 10 year warranty - the amount and quality of sacrificial anodes.

  6. mackstann | | #6

    There are premium gas water heaters with stainless tanks. I'm not sure what they cost, or if they'd last as long as a Marathon, but they're probably worth checking into.

  7. PAUL KUENN | | #7

    Rube G - Ouch!

    That's like saying Vermont cheese is better than Wisconsin cheese (486 varieties and hundreds of international awards). No way, No!

    Natural gas is poisoning thousands of lives and destroying land, gives billionaires plenty to laugh at while we wretch in their wake of destruction. I'll buy the PV thought for a heat pump style tank heater but never any fossil fuel system. Makes a simple, very efficient hot air collector (i.e. Sunsiaray) or two in a roof top or ground mount system seem inexpensive and you'd have much less upkeep than the past liquid thermal collectors.

    While our system keeps the house at 65F during the day (while we're gone and thermostat off) plenty of hot water is supplied through the exchanger to run floor heating in the night. Yes, of course it takes sun to do that (70% of the year). With a good tank, you're good for 50-70 years. That's a lot of gas or electric water heaters... and I'm not harming any one in doing so. OK it does take an aluminum mine and some infractions upon the environment, but not like gas delivery.

    Heck, four collectors together were melting the PC plastics in an office before we added more venting. You can't get that much heat out of water. BTW, not our fault, we told them we weren't done installing.

    A small heat pump takes care of the seemingly endless winter sunless days. Yes, we do have two PV systems to take care of the heat pump and other household amenities.

    PK Chedder head - way beyond net zero and healthier for it

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