How to Flush a Water Heater in Arizona's Hard Water

Arizona water carries a lot of dissolved minerals. In a water heater, those minerals settle at the bottom as sediment, which lowers efficiency and shortens the tank's life.

The Short Answer

Flushing a tank water heater once a year removes sediment and helps it last longer. In very hard water, twice a year can help. If the heater is old or the drain valve is stuck, call a professional rather than forcing it.

Why Sediment Builds Up

Heated hard water leaves calcium and magnesium behind. The layer at the bottom insulates the water from the burner or lower element, so the unit works harder, makes popping noises and can overheat.

Safe Steps for a Tank Flush

1. Turn off power to an electric heater, or set a gas unit to pilot.
2. Close the cold water supply valve.
3. Attach a hose to the drain valve and run it to a safe drain or outside.
4. Open a hot tap in the house, then open the drain valve and let the tank empty.
5. Briefly open the supply to stir remaining sediment, then drain again until water runs clear.
6. Close the drain, refill the tank fully before turning power back on.

Never turn an electric element on while the tank is empty.

When Not to DIY

If the drain valve is plastic and brittle, the tank is very old, or water will not run clear, stop and call a pro. Heavy sediment can also mean the tank is near the end of its life. Read how long water heaters last.

Other Maintenance

Check the anode rod, test the relief valve and consider a water softener for the whole home. See our noisy water heater service if you hear popping.