How to Flush a Gas Hot Water Heater Tank

Sediment and mineral deposits can build up in your gas water heater's tank, especially if you have hard water. This sediment also can affect the quality of water in the tank. Flushing your tank will improve the quality of water in the heater, allow the heater to hold more water and avoid blockages at the drain valve.

Things You'll Need

• Garden hose

Instructions

1. Open the outer and inner doors on your gas water heater.

2. Set the gas control knob to "Pilot" by turning it counterclockwise.

3. Connect a garden hose to the drain valve at the bottom of your heater's tank.

4. Run the other end of the garden hose to a drain or outside of your home.

5. Turn off the cold water valve to the water heater.

6. Lift the temperature/pressure relief valve at the top of the tank and leave it open.

7. Open the drain valve at the bottom of the tank.

8. Allow the tank to completely drain.

9. Remove any sediment blockages in the drain valve by closing the temperature/pressure relief valve and opening the cold water valve. When the water exiting the garden hose is clear, you have removed all the sediment.

10. Close the drain valve.

11. Remove the garden hose.

12. Close the temperature/pressure relief valve.

13. Turn on the cold water valve and allow the tank to completely fill.

Tips & Warnings

• You can drain the garden hose into a hard plastic bucket. When the bucket fills, close the drain valve, remove the hose and empty the bucket. Continue draining the tank by reinserting the hose into the bucket and opening the drain valve.

• If the sediment at the bottom of the tank has hardened into large pieces, turn off the cold water valve and drain the tank as much as possible. Remove the garden hose and insert a long screwdriver into the drain valve to break up the hardened pieces of sediment.

• The water coming out of the hose can be very hot and could scald you.

References

• Chili Pepper Appliance: Water Heater Flush - How to Flush a Gas or Electric Water Heater