Prepare the Tank for Maintenance
Before you jump right in, take time to prepare the water heater:
- Turn off the power source (natural gas or electricity).
- Close the water inlet and give the water time to cool down.
- Turn on one hot water faucet to a slow drizzle. Leave this on for the duration of water heater maintenance to release pressure within the tank as you work.
Test the Temperature and Pressure (T&P) Relief Valve
The T&P valve is typically located on the upper half of the tank. When working properly, it automatically releases pressure if levels climb high above normal. To test the T&P valve:
- Lift up on the lever. Let go and allow it to rapidly snap back into place.
- Listen for a gurgling sound as the valve releases some water into the drain tube.
- If you hear no gurgling or the valve does not snap back into place, have it replaced.
Drain the Tank
Flushing out the water heater drains sediment from the bottom. This maintenance step increases efficiency, prevents corrosion and lengthens the appliance’s life. A full flush is the most comprehensive way to drain the tank, but a mini-flush twice a year is effective as well. To drain the tank:
- Place a bucket under the drain valve, located near the bottom of the tank.
- Turn the handle counter-clockwise. In the case of water heaters with a handle-less stem, insert a flat blade screwdriver and then turn the valve.
- Close the valve and drain the bucket outside or down the kitchen sink.
- Repeat the process until you have flushed out a few gallons and the water runs clear.
- Groaning and gurgling sounds are normal during this process as air enters to replace the water you’re draining out.
Check the Anode Rod
Corrosion feeds on the tank’s most vulnerable parts. That’s the entire function of the anode rod: to suffer corrosion so the stainless steel tank can last longer. The usual life expectancy of an anode rod is four to six years. After your tank is two or three years old, it’s wise to begin checking the anode rod once year. Complete the following steps after doing the mini-flush when you have already drawn off a few gallons of water:
- Examine the top of the water heater. If present, remove the cap covering the anode rod’s connection point.
- Turn the rod counter-clockwise with a socket wrench until it clears the threads.
- Lift the anode rod straight up, keeping it from knocking against the inside of the tank as you do so.
- Inspect the rod carefully. Some pitting and surface corrosion is normal, but if large chunks are missing, it’s time to replace it.
- Wrap the thread of the existing or replacement rod in Teflon tape, carefully reinstall it back in the hole and tighten it securely in place.
Restart the Water Heater
You’re finished with water heater maintenance! It’s time to get it back up and running again with these steps:
- Make sure the drain valve is tightly closed.
- Open the water inlet so the tank can refill itself.
- Restore power by turning the gas or electricity back on. Relight the pilot if applicable.
- Set the temperature to 120 degrees instead of the standard 140 degrees. At this temperature, you’ll save energy and prevent scalding at the tap without fearing microbial growth in the tank.