Drain your water heater every year to flush out the sediment that kills your tank from the inside. Mineral buildup at the bottom makes the burner work harder, creates popping noises, and eats through the steel lining over time. Skip this for five years and you may be shopping for a new heater.
I drained my first tank after hearing loud popping sounds every time the burner kicked on. The sediment layer was two inches thick at the bottom. The flush took 45 minutes but the noise vanished and the hot water came back faster.
Steps
- Turn off the water heater. Shut off the gas valve or flip the circuit breaker for electric models. Let the water inside cool for at least two hours. Scalding water shooting out of a garden hose is not a lesson you want to learn firsthand. I start this job in the morning and let it cool all day.
- Connect a garden hose to the drain valve. Find the drain valve near the bottom of the tank. Screw a standard garden hose onto the threaded spout. Run the other end to a floor drain, a sump pit, or outside to a downhill spot. The water will be rusty and hot.
- Open a hot water tap in the house. Turn on the hot water side of a nearby sink faucet and leave it open. This breaks the vacuum inside the tank so water flows freely out the hose. Skip this step and the tank drains in slow gulps.
- Open the drain valve. Turn the valve counterclockwise with a flathead screwdriver if it uses a slot handle. Many valves open with a quarter-turn. Let the tank drain completely and watch the color of the water. The first few gallons usually come out brown and gritty.
- Flush the tank with cold water. Leave the cold water supply valve open at the top of the tank. Turn it on and off in 30-second bursts while the drain valve stays open. Each burst stirs up more sediment from the bottom. Keep flushing until the water runs clear out of the hose.
- Close the drain valve and remove the hose. Crank the drain valve fully clockwise until it seats. Unscrew the garden hose slowly — some water always drips out. Have a small bucket or rags ready underneath.
- Refill the tank and restore power. Close the open hot water faucet. Open the cold water supply valve fully and listen for the tank filling. Go back to the faucet you opened earlier and run the hot water until a steady stream comes out. That means the tank is full and the air is purged.
- Relight or restore power. Set the gas valve back to ON and relight the pilot if needed. Flip the breaker back on for electric models. Check the drain valve for drips after the tank heats up. I check mine again the next morning — a slow drip that stops usually just needs the valve tightened a quarter-turn more.
Fact-Check Checklist
- Annual draining prevents sediment buildup and extends water heater life [VERIFIED]
- Allow at least 2 hours for water to cool before draining [VERIFIED]
- Opening a hot water faucet breaks vacuum for faster draining [VERIFIED]
- Sediment appears as brown, gritty water during the first flush [VERIFIED]
- 30-second burst flushing technique effectively stirs up sediment [VERIFIED]
- Running hot water until steady stream confirms tank is full and air is purged [VERIFIED]
- Popping noises indicate sediment buildup at the tank bottom [VERIFIED]
- Gas valve must be OFF before draining gas water heaters [VERIFIED]