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Mineral deposits build up quickly in hot water heaters, This reduces both the efficiency and the life of the hot water heater.

A water heater should be flushed at least once every six months, or every three months in areas with high mineral concentration in the water supply.

Tools & Materials Needed

  • Garden hose.

Steps To Flush a Hot Water Heater

  1. Connect a garden hose to the drain valve.
  2. Run the other end of the hose either to a drain or to the outside the home. A drain can be a floor drain in a laundry room, a nearby bath or shower, or a laundry tub. If the hot water heater is located in a garage or near an outside door, the hose can be run outside. If run outside, do not flush the hot water onto grass or plants. Just let the water run down the driveway.
  3. If you have a gas water heater, make a note of the temperature setting, then turn the gas valve setting to Pilot. Don’t turn it off or you may have to re-light the pilot flame. If you have an electric hot water heater, shut off the power to the unit.
  4. Open the drain valve all the way and let it run for about two minutes. The valve on your unit may use either a screw or a knob.
  5. After two minutes has elapsed, close the water supply valve. This is usually located on a pipe above the hot water heater.
  6. Go to the closest sink and turn the hot water on. Shutting off the water supply in conjunction with turning on the hot water at a nearby sink allows the hot water heater to drain.
  7. After the water heater has drained, turn the water supply valve back on. Allow the water heater to flush with fresh water for another two minutes.
  8. Close the drain valve. Let the water heater refill itself. You should hear the water running as the tank fills.
  9. Go to the sink faucet and wait until all the air has been purged from the water lines. You will hear gurgling sounds and the flow of water will be intermittent while the air is being purged. When all the air has been purged and the water flow is steady, shut of the sink faucet.
  10. For a gas heater, turn the gas valve setting to On. If you changed the temperature setting, adjust it to the original setting. For an electric heater, turn on the power.
  11. Disconnect the garden hose.

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