Feb. 3, 2017
As with any appliance, water heaters need regular maintenance to keep them operating at peak efficiency and to help them last as long as possible. This is especially true for heaters that are more energy efficient than standard models. If they are not properly maintained, they will become less and less efficient as time goes on. Here are some tips for maintaining conventional storage-tank water heaters.
Review the Paperwork
Before starting, read the “Use and Care” manual that came with the appliance. It will spell out specific maintenance tasks. When in doubt, consult the manual. If you don't have yours, you can usually download a copy from the water heater manufacturer's website.
To perform most maintenance tasks, you will need to know how to shut off the water and the power to the water heater. There should be a shutoff valve in the cold water line near where it enters the water heater. If there isn't one there, you will need to turn off the water to the entire house.
Storage tank water heaters are powered by either electricity or natural gas. Electric models should have a cutoff switch near the unit. If there isn't one, turn the power off at the panel box. Gas models will have a gas pipe attached to the unit as well as a flue that vents combustion gas to the outside. The gas line will have a valve on it. Close the valve to cut off the supply of gas to the unit.
Caution: Keep in mind that water in the tank is very hot. Be aware of this and avoid contact with the water.
Common Maintenance Tasks
Drain Sediment that Collects in the Tank. Cold water that flows into the storage tank contains some impurities that can settle on the bottom of the tank. Over time, the sediment can interfere with the workings of the water heater. Most manufacturers recommend draining some of the water through the drain valve at the bottom of the tank. Here's how it is done.
- Turn off the water and the power to the tank.
- Connect a garden hose to the drain valve on the water heater—it's near the bottom of the tank—and run the hose to a drain.
- Open a hot water tap nearby and leave it open.
- Open the drain valve and drain some water until it runs clear. Professional plumbers often turn the water on and off to stir up the sediment on the bottom of the tank.
- When the draining water is clear, close the drain valve and turn the water to the tank back on. You will know the tank is full when water runs through the tap you left open.
- When the tank is full of water, close the tap and turn the power to the water heater back on. Do not turn on the power before the tank is full because heating elements inside the tank could be damaged if not covered with water.
Test the Temperature-Pressure Relief Valve. This valve will be near the top of the tank and may be attached to a long tube that runs almost to the floor. The valve is designed to relieve unsafe pressure that builds up inside the tank. Plan on testing it at least once a year. Here's how.
- Place a small bucket at the end of the extension tube.
- Lift the valve's handle up so that it is sticking straight out parallel to the floor. There should be a release of steam pressure and water. If nothing happens, the valve may be defective. Consult a plumber to fix the problem.
- If the valve works, return the handle to its original position.
Inspect and Replace the Anode Rod. This rod is made of magnesium or zinc, or some combination of metals, and is suspended inside the tank. It's a sacrificial component that attracts corrosive elements in the water so that those elements do not attack the lining of the storage tank. Over time, the rod becomes too corroded to do its job and must be replaced. Plan on inspecting them every few years. Here's how to check and replace the rod.
- Shut off the water to the heater and turn off the power as well.
- Open a hot water tap nearby, and leave it open.
- Drain four or five gallons from the tank through the drain valve. This will help prevent water from splashing up on you when you remove the rod. Don't drain too much water, because the water's weight will help keep the tank steady when you remove the rod.
- The rod is threaded to the top of the tank. It may take some searching to find it. If you can't find it, consult the manual.
- Most rods can be removed by using a 1-1/16-inch socket wrench and breaker bar. These rods can be stubborn, so it helps to have someone hold the water tank in place while you work.
- Pull out the rod carefully. If sections are missing, replace it.
- The new rod should be the same length as the old one. If overhead space is tight, you can install a segmented rod that allows you to fold the sections to make installation easier.
- Apply some Teflon tape to the threads of the new rod. Lower it into place and tighten.
- Turn the water on.
- When the tank is full, water will be running from the hot water tap you left open. Close the tap.
- Turn the power back on.
These maintenance tasks can extend the life of your water heater and keep it running as efficiently as possible. For a complete guide to choosing and maintaining a water heater, visit this water heater guide from Coldwell Banker and Home Depot.
Fran Donegan writes home- and garden-related content for numerous digital and print publications. He is the author of the books Pools and Spas and Paint Your Home. To learn more about whole-home water heaters like those referenced by Fran, please visit the Home Depot website.
This blog was developed by The Home Depot. All posts, sponsored and un-sponsored have been reviewed and approved by the Sustainable Community Media Editorial Team to ensure quality, relevance/usefulness and objectivity.