Water heaters 101 


Question: How long should a water heater last? And what can you do to make a water heater more energy efficient?

Answer: It’s hard to say how long your water heater will last. Certified home inspectors estimate the life span to be about 10 years. Some manufacturers suggest 12 to 13 years, but I had a water tank that lasted more than 40 years before the heating element finally gave out. That said, it’s wise to replace a water heater before it fails because sometimes failure includes a ruptured tank or a massive leak that can do a lot of damage.

The lifespan of a conventional water heater (one with a tank) depends on factors such as the volume of water cycled through it, the hardness (mineral content) of the water and the tank’s interior coating. Many water heaters come with a warranty as long as 12 years. Presumably, a longer warranty indicates higher quality and the chances of longer life. These warranties usually only cover the cost of a replacement tank; they typically do not include the cost of labor to install it or the costs from flood damage if the tank fails.

Mineral deposits on pressure release valves or corrosion on fittings coming out of the water heater are signs of leakage that should be addressed.

There are a few warning signs that your water heater tank or heating element may be failing:

  • Water leaking from the tank or pooling on the floor underneath it;
  • Rust, corrosion or mineral deposits around fittings or release valves; or
  • The water temperature from your faucets is dropping.

Most experts believe that an important water heater maintenance practice is to drain the tank every year or two. Allstate.com provides an excellent step-by-step guide. However, Ken Maleski, the residential energy adviser at Central Electric Cooperative in Pennsylvania, recommends that if your tank has not been drained in the past six to seven years, you should avoid doing so because draining could remove sediment in such a way that a leak could develop.

Insulating your water heater and keeping the temperature at 120 degrees or below are two ways to save money on your utility bill.

Here are a few simple steps you can take to increase the efficiency of your water heater:

  • Insulate the first six to 10 feet of easily-accessed hot water line where it exits the tank.
  • If the tank is warm to the touch or is in a cold location like your garage, consider insulating it with a heater blanket. But first, check the owner’s manual to make sure doing so won’t void the warranty. If you have a gas or propane water heater, be careful the blanket doesn’t block the unit’s air supply.
  • Keep your water temperature at 120 degrees or less. This will help you save money on your heating bill and ensure longer life for pipes and gaskets.

Opportunities to save money on your hot water budget abound throughout the house. Showering uses almost 17 percent of our indoor water use, so you can save money by installing efficient shower heads. Replacing older dishwashers and washing machines with more efficient models will also reduce your energy bills. You should repair any leaky faucets, as a drip every second can add up to $35 a year.

When it’s time to purchase a new water heater, there are many options available. Be sure to check with your local electric co-op. Last but not least, check out Energy.gov’s excellent article on selecting a new water heater.

This column was co-written by Pat Keegan and Brad Thiessen of Collaborative Efficiency. For more information on water heaters, please visit: www.collaborativeefficiency.com/energytips. For more energy efficiency tips, visit: smartenergytips.org.