How to Clean a Hot Water Tank

The sediment and mineral deposits from your water supply can build up in your water heater's tank over time, reducing its efficiency and longevity.
Don't forget to clean your hot water tank!Don't forget to clean your hot water tank!
Draining the hot water tank on a regular basis -- at least one a year -- to get rid of those deposits will keep it running in top condition.

Step 1

Shut off the power to an electric water heater. Turn off the gas if your heater is a gas-powered model.

Step 2

Turn off the cold-water supply line to the water heater tank. Screw a garden hose to the drain valve found at the bottom of the tank. Run the other end of the hose outside your house, to a spot that's lower than the bottom of your tank. Place the hose in the bucket.

Step 3

Open the drain valve where you connected the hose. Let the water drain out of the tank. Check the bucket to see if any sediment drained out. If there's a lot of sediment, shut off the drain valve. Refill the tank by turning on the cold-water valve, then shut off the valve and start draining the tank again. Repeat as necessary until the water runs clear.

Step 4

Let the tank finish draining. Turn off the drain valve. Disconnect the garden hose.

Step 5

Turn on the cold-water valve and allow the tank to fill. Once the tank has filled, turn on the electricity or gas to the heater.

Things You Will Need

  • Garden hose
  • Large bucket

Tips

  • If your water heater is in a basement, you can drain the tank into the floor drain. If there's no floor drain, you'll need to use an electric pump to drain the water outside the house.
  • If the drain valve clogs, open the cold-water valve briefly to flush out any debris.
  • In areas with hard water, monthly flushing may be recommended.

Warnings

  • Don't turn on the power when the water heater is empty or partly-filled; the elements could burn out.
  • If you have a gas tank and don't know how to relight the pilot light, call in a professional to do it.