Have an HVAC Technician Flush Sediment from Your Water

Have an HVAC Technician Flush Sediment from Your Water Heater

November 19, 2015

Hard water and your water heater don't play well together. Here in Des Moines, our local water supply contains about 150 milligrams per liter of dissolved minerals. That puts us at about mid-range on the national water hardness scale. Hard water isn't a health hazard. However, it is a threat to the efficiency and service life of water heaters. A water heater generally lasts about 10 to 12 years. In a hard water region, however, they often require replacement long before then.

The Hard Facts

When exposed to heat, dissolved minerals in hard water solidify and settle to the bottom of the tank, forming a layer of sediment. This layer absorbs heat generated by the burner, causing the burner to run longer cycles to heat water to the proper temperature. The tip-off is often increasingly higher gas bills. Meanwhile, sediment accumulation in the tank also accelerates the process of corrosion, triggering leakage and even tank rupture. Early water heater replacement is usually the only recourse.

flushing by a qualified technician removes sediment before it turns rock-hard.

  • First, the heater is turned off at the gas valve and the cold water inlet valve is shut.
  • A garden hose is connected to the tank drain faucet. The other end is routed outdoors to an area appropriate for discharging drain water.
  • The technician opens the valve and begins draining the tank. To admit air and increase the draining force, he or she will usually hold open the spring-loaded temperature and pressure relief valve, too.
  • When the tank is fully drained, the cold water valve will be quickly opened and closed multiple times to enhance the flushing action and purge remaining sediment.
  • After closing the drain valve and disconnecting the hose, the technician will open the cold water inlet and re-light the heater.
  • When the water is up to temperature, he or she will verify the thermostat setting for scald prevention and verify proper operation of the temperature and pressure relief valve.

For annual service to maintain the life expectancy and energy efficiency of your water heater, contact Lozier Heating & Cooling.

Our goal is to help educate our customers in the greater Des Moines, Iowa area about energy and home comfort issues (specific to HVAC systems). Credit/Copyright Attribution: "Minerva Studio/Shutterstock"