How Long Does a Water Heater Usually Last?

For most homeowners, their water heater is their most-used appliance but rarely given much thought until it fails. Your standard tank heater works continuously day and night to provide your home with hot water and it will give many indications when it’s under too much strain and preparing to give out. Watching for these warning signs and ensuring your heating unit gets routine maintenance can extend the life of your heater and prevent the inconvenience or even water damage that comes from unexpected failure.

How Long Do Water Heaters Last?

A common question among homeowners is how long water heaters can be expected to last. After all, you don’t want to waste money replacing an appliance that still has life, but you also don’t want the consequences of a flooded laundry room or replacing flooring. In general, tank water heaters last for 8 to 12 years. Tankless water heaters can last for 20 years or longer because they do not have a tank or work continuously.

If you aren’t sure about the age of your heater, check its serial number. The serial number is likely a letter with a long series of numbers. In most cases, the letter represents a month (A for January, B for February, etc) while the following two numbers indicate the year of manufacture. A serial number that begins with 608 indicates it was manufactured in June 2008.

Extending the Life of Water Heaters

Proper maintenance can help water heaters last as long as possible without premature failure. While the expected lifespan of a heater is 8-12 years, it’s possible for a well-maintained unit to last for 17 years or longer. How long water heaters last has to do with aging; the more minerals that are allowed to build up, the sooner the unit will fail.

Water heaters should be drained at least once a year, but three or four times per year is even better to prevent sediment and calcium from building up inside the tank and causing leaks and strain on the system.

The anode rod, or the sacrificial rod in the tank that attracts minerals and prevents tank corrosion, should be changed every 6 months as a proactive step to protect the tank.

With electric water heaters, the heating elements and thermostat should be replaced as needed to keep the unit working efficiently. With gas heaters, the thermal coupling that keeps the pilot light on and the gas valve should be replaced when necessary.

Signs Your Water Heater is Failing

Your heater won’t simply fail without warning; there will be at least a few signs that your heater is preparing to give out completely or needs repairs. You can avoid water damage to your home and disruption to your life by watching for the following signs:

  • Rumbling and loud noises. As the heater ages, a thick layer of sediment will accumulate on the bottom. This sediment hardens over time as it is repeatedly heated. Hardened sediment doesn’t just make your heater less efficient, it also damages the metal tank and leads to a rumbling noise during operation.
  • Rust-colored water. If your hot water has a rusty color, it’s a sign the heater is rusting away from the inside and may develop a leak in the near future. The rust may also be coming from failing galvanized pipes.
  • Water near the heater. If you see moisture or a puddle of water around the heater, there may be a tiny leak in the tank itself. Water can escape these tiny leaks as the metal expands with heat. A leaking tank cannot be repaired and it’s only a matter of time before the leak gets worse and your home gets flooded.
  • Smelly or cloudy water. This is often caused by mineral deposits in the heater traveling through your hot water lines and creating a metallic aroma and cloudy hot water.
  • Insufficient hot water. Running out of hot water too quickly or water that is never hot is a sign that the heating elements need to be replaced. It can also be a sign that your appliance is simply reaching the end of its life.
  • Heater is 10+ years old. In general, water heaters that are 10 or more years old should be considered for replacement as this is close to the end of the expected lifespan and appliance failure can lead to water damage.

Benefits of Replacing Your Heater Sooner

Sometimes you don’t have a choice but to replace your water heater, but there are also good reasons to replace your appliance before the recommended ten-year age mark.

One of the best reasons to upgrade to a new heater is reducing your energy consumption. According to the Department of Energy, water heaters are the second-greatest use of electricity in the typical home, accounting for a whopping 18% of the average electric bill. If your appliance is several years old or it has a low EF rating, you may be throwing away money. Investing in a new heater with a higher EF rating can help you save money every month.

There are other good reasons to upgrade your heater:

  • Your heater has bad placement and its location can cause serious damage if the tank leaks
  • You want to ensure good water quality. Aging tanks and sediment build-up can lead to smelly or rust-colored water from corrosion.
  • You want to change from a standard tank to a tankless heater.
  • You want to avoid the inconvenience of running out of hot water without warning.

If your water heating unit is approaching the end of its life, replacing it can help you avoid the inconvenience and potential property damage of failure while reducing your energy consumption. Don’t ignore warning signs that your heater is getting ready to fail; replace it when it’s time to save yourself a major headache later.