How Long Does a Water Heater Last?

Like all home appliances, how long a hot water heater lasts can depend on a number of factors including what type of water heater it is, how often you use it, how often maintenance is performed on it, what type of climate you live in, the quality of your home’s water, and how well the water heater was initially installed.

It’s important to always pay close attention to your water heater’s performance and condition, but it is especially crucial towards the end of your water heater’s life so that you can be prepared when it may be time for a new unit, as well as to ensure that your system is working as efficiently and effectively as it should be.

In this blog post, we’ll explore some general rules of thumb in regard to how long different types of water heater tank styles can last, what can lengthen or shorten the lifespan of your water heater and the signs you can look for that may tell you when it’s time to replace your current water heater.

Traditional Tank and Tankless Units

On average, traditional storage tank water heaters last between eight to twelve years. Inside of each tank is an anode rod that protects the interior lining of the unit through a process called electrolysis. The electrolysis causes the corrosive particles that naturally occur inside of the tank to be attracted to the rod.

When the rod itself has corroded so much that it can no longer function properly, the corrosive particles will instead start to settle at the bottom of the tank. This will eventually destroy the lining of the tank and ultimately lead to the old water heater needing to be replaced.

The life expectancy of a tankless water heater can be up to 20 years, sometimes even longer depending on the unit. Because tankless systems do not continuously heat and store hot water like their storage tank counterparts, instead heating the water as it’s needed, they do not corrode as fast and they last much longer. However, tankless water heaters do eventually succumb to corrosion as well, which is a major cause as to why they end up needing to be replaced.

You may not know exactly how old your water heater is, and that’s okay. If you don’t have the documentation for the system, locate the serial number on the upper portion of the water heater to help determine its age. The majority of water heater manufacturers follow a standard procedure when it comes to listing the age of the unit in its serial number.

The first letter will stand for the month it was manufactured (A = January, B = February, and so on), while the two digits after the letter denote the year (10 = 2010, 11 = 2011, etc.). You can confirm that this rule applies to your water heater as well by checking the manufacturer’s website.

Signs Your Water Heater is Aging

It’s important to start thinking about replacing your water heater during the last two years of its life and/or when it starts to show various signs of aging so that you are prepared when the time comes, and you aren’t surprised by an unexpected shock of cold water. Warning signs that show your water heater is aging include:

• Water pooling around the base of the tank. Finding water at the base of your water heater tank does not necessarily mean it’s time to replace the entire system. First, check to see that all of your fittings and valves are tight and functioning properly to ensure that the leak isn’t coming from a loose or old seal, both of which are common yet simple problems to fix. If your fittings and valves are in good shape, the leak could be coming from a crack or a corrosion-related issue within the tank itself.
• Discolored hot water. If the water coming from any of your hot water faucets is tinged red, yellow or brown, this could signify rusting. If the discoloration also occurs when cold water is running, this most likely means that your pipes are rusty. If the discoloration only occurs when hot water is running, this could mean that your water heater tank is rusty from internal wear and corrosion.
• Banging or rumbling coming from the water heater. Most homeowners don’t know that manufacturers and plumbers recommend draining your water heater once a year to flush out sediment buildup, prolong the unit’s life and ensure peak efficiency. If you haven’t been flushing your water heater annually, calcium buildup from hard water will collect at the bottom of the tank, eventually forming a thick crust that can cause the water heater to creak and make loud, abnormal noises when running. This is normally only present at the end of a water heater’s life.
• To avoid calcium buildup and to extend the life of your water heater, follow our step-by-step guide on how to drain your own water heater.
• A drop in water temperature. If your water heater isn’t performing its main join and heating up your home’s water at the same level it normally does, this could mean that it’s nearing the end of its usability. However, a drop in water temperature is another problem that can be caused by an issue with the heating element, a faulty thermostat, a blown fuse or a tripped breaker. Rule out all possibilities before replacing your unit.

At the end of the day, while each of these issues may signify the end of your water heater’s service life, there could be other reasons why they are occurring.

Whenever you experience a serious issue with your water supply or water heater, especially if you think you system could be up for a replacement, call a professional plumber to help you pinpoint the exact source of the problem as well as to help you determine whether or not it is in fact time for you to purchase a new water heater.

Remember to also utilize the skills of a trusted plumber to perform water heater maintenance to get as many years out of your water heater as possible.