How to Flush and Maintain a Tank Water Heater

Sediment is the silent enemy of your water heater. Over time, minerals from your water supply settle at the bottom of the tank, creating a layer of insulating sludge that forces your heating elements to work twice as hard to reach the set temperature. If you have ever heard a popping or rumbling noise coming from your utility closet, that is steam bubbles escaping through the sediment layer, and it is a clear sign your tank needs attention. Performing a full flush once a year keeps your water heater running at peak performance and prevents premature failure of the tank lining. This process is straightforward, requiring only a garden hose and a few basic tools. When done correctly, you ensure better water quality and significant energy savings throughout the year.

Kill the Power First. If you have an electric heater, flip the circuit breaker at your main panel to off. If you have a gas unit, turn the gas control knob on the heater to the Pilot setting or off.
Route Your Drain Line. Attach a standard garden hose to the drain valve located at the bottom of the tank. Run the other end of the hose to a floor drain, a basement sump, or outside to a safe location.
Break the Vacuum Now. Locate the temperature and pressure relief valve near the top of the tank and lift the lever. This breaks the vacuum inside the tank, allowing the water to drain freely.
Empty the Tank Completely. Open the drain valve at the bottom of the tank using a flathead screwdriver or the built-in handle. Let the water flow out completely until the stream stops.
Stir and Clear the Sludge. Briefly turn the cold water supply valve back on for 30 seconds to stir up any remaining silt at the bottom. Repeat this cycle until the water running through the hose appears clear.
Refill and Repower. Close the drain valve, disconnect the hose, and close the pressure relief valve. Open the cold water supply to fill the tank, and once water runs steadily from a hot water faucet in your home, restore power or gas.