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Smart Choices

Caring for Your Water Heater


Photo of two men installing a water heater.

In February, we published a list of routine home maintenance tasks to perform to keep your systems operating at peak performance. One task we did not include on the list, but promised to revisit, is hot water heater maintenance.


Flushing the water heater tank removes mineral sediment that accumulates in the bottom of the tank. If it’s not completed frequently enough, the mineral buildup may cause banging or rumbling noises as water moves through the tank. If you wait too long to flush the tank, the sediment will make it harder to complete the task later. Even worse: Your tank (if it’s a steel tank) may rust out prematurely.


If you have a newer water heater model: Some home maintenance lists recommend flushing the tank annually, while others, such as the RHEEM Marathon Use and Care Manual, recommend that a few quarts or liters of water be drained from the bottom of the tank every month to remove mineral deposits.

The deposits that settle in the basin (the bottom of the water heater) come from mineral solids that are suspended in water.

If you start immediately after installation, you should have no problems with the accumulation of the mineral deposits, and you’ll keep your tank in good condition and working well.


If your water heater hasn’t been flushed for years: Some plumbers advise against flushing at all by this point because the flushing action could activate leaks. The theory is this: Tiny fissures in the base of the water heater may have filled with sediment that helps prevent leaks, particularly in a gas water heater as the flame has been baking the steel bottom. Flushing out the sediment could remove some of the protection against leaking (in other words, the sediment that has been preventing holes from forming). If your water heater hasn’t been flushed for years, it would pay to ask one or more plumbers in your area for an opinion on how to proceed.


An additional task for steel water heater tanks: Most steel water heater tanks have a thin glass lining to protect the metal from corrosion. Since the lining eventually cracks, tanks have a second line of defense against rust: a long metal “anode rod” that attracts corrosive elements from the water. When the rod becomes so corroded that it can no longer do its job, the tank soon rusts out, leaks and needs to be replaced. However, replacing the water heater anode rod before it fails, about every five years can double the life of the heater. Because the rod can be difficult to break loose and must be installed with liquid Teflon pipe thread sealant (not tape), consider hiring a qualified plumber.



Photo features a Marathon water heater in a home basement.

Investigate the low maintenance option for your next water heater: Contact your cooperative to learn more about the advantages of the low-maintenance, Marathon electric water heater – the last water heater you’ll ever need to buy! The Marathon features a seamless, blow-molded polybutene inner tank that will not rust or corrode, and the heater’s innovative construction methods deliver a long life, high efficiency and good looks, too! It’s warranted1 not to leak as long as you own your home and does not require an anode rod. If you enroll in our load management program, we offer incentives to make this premium water heater very affordable.

  • A lifetime warranty is provided to original customer in a residential application after online product registration is complete. Registration must be completed within 90 days of installation.

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