Step-by-Step Guide: How to Flush a Water Heater

Regular maintenance is crucial to keeping your water heater running efficiently. One of the most essential tasks is flushing your water heater to remove sediment buildup, which can drastically improve performance and extend its lifespan. Over time, minerals and sediment accumulate in the water tank, particularly in areas with hard water. 

This buildup reduces your unit’s heating efficiency and forces the water heater to work harder to heat the same amount. In the worst cases, this can damage the heating elements or cause the unit to overheat and fail prematurely.

Flushing every six months may be necessary for homes with very hard water to keep the unit running smoothly. This maintenance benefits gas and electric water heaters, as sediment buildup can affect either type of system. 

For expert assistance or to explore our professional services for your water heater, visit InMotion Heating to ensure your system is well-maintained and running efficiently. Follow our comprehensive steps to keep your water heater performing optimally, providing consistent hot water for your home.

Step 1: Turn Off the Power or Gas Supply

Turn off the power supply to begin the process safely. If you have an electric water heater, switch off the circuit breaker at your electrical panel. 

For gas water heaters, locate the thermostat dial and turn it to the “pilot” position or switch the gas valve off entirely. This ensures that your water heater will not continue to heat while you flush the tank, preventing damage to the unit and ensuring your safety.

Step 2: Shut Off the Cold Water Supply

Next, turn off the cold water supply to the water heater. This valve is typically located near the top of the water heater. Shutting off the cold water stops the water flow into the water tank and allows you to drain the existing water safely without introducing more water into the system.

Step 3: Connect a Hose to the Drain Valve

Once the cold water supply is turned off, locate the drain valve near the bottom of the water heater. Attach a garden hose to this drain valve, ensuring it is securely fastened to avoid leaks. Position the other end of the hose to a floor drain, outdoor area, or large bucket to collect the water as you flush the tank.

Step 4: Open the Drain Valve and Flush the Water

With the hose in place, open the drain valve to allow water to start flowing out of the tank. Opening a hot water faucet in your home (such as at a sink) will help release pressure in the system and allow the water to drain more smoothly. 

As the water flows, sediment and debris built inside the tank will be flushed out. Be cautious, as the water exiting the tank can be very hot.

Step 5: Flush the Tank with Cold Water

Once the initial water has drained, briefly turn the cold water supply on to flush out any remaining sediment. This step will help remove stubborn buildup that may not have been cleared during the first drainage. 

Let the cold water run through the tank for several minutes, ensuring the water running out of the hose is clear and debris-free. This step is critical for maintaining the long-term efficiency of both gas and electric water heaters.

Step 6: Close the Drain Valve and Refill the Tank

After you have fully flushed the tank, close the drain valve securely. Detach the hose from the drain valve and ensure the valve is tightly sealed to prevent leaks. Once the valve is closed, turn the cold water supply back on to allow the water tank to refill. 

This will take several minutes, depending on the size of your water heater. While the tank is refilling, check the drain valve to ensure no leaks.

Step 7: Restore Power or Gas Supply

After the tank has been refilled completely, it is time to restore power or gas to your water heater. Switch the circuit breaker on for electric water heaters at your electrical panel. Turn the thermostat dial from “pilot” to your desired temperature setting for gas water heaters. Ensure the pilot light is lit and the gas supply is restored before turning the thermostat to its usual position.

Step 8: Test the Water Temperature

Finally, test your hot water by turning on a hot water faucet. Allow the water to run for several minutes to ensure that the temperature is correct and that there are no issues with the heating elements or gas burners. Your water heater should now function more efficiently, with improved heating performance and a longer lifespan.

Additional Tips for Maintaining Your Water Heater

While flushing your water heater is a critical task, there are other maintenance steps you should consider to prolong the life of your unit:

• Check the Anode Rod: The anode rod helps prevent corrosion inside the tank. Inspect and replace it if necessary, typically every two to five years.
• Test the Temperature and Pressure Relief Valve: This safety valve prevents the tank from overheating or building up too much pressure. Test it regularly to ensure it’s functioning correctly.
• Set the Thermostat to the Right Temperature: For optimal performance, set the thermostat to around 120°F. This temperature reduces the risk of scalding and prevents the water heater from working harder than necessary.

Common Issues After Flushing a Water Heater

If you experience any problems after flushing your water heater, here are a few common issues and their potential solutions:

• No Hot Water: If you aren’t getting hot water after flushing, ensure the power or gas supply has been properly restored. For gas water heaters, check that the pilot light is lit.
• Water is Too Hot: Adjust the thermostat setting if the water temperature is too high. Make sure the thermostat is not moved during the flushing process.
• Water Leaks from the Drain Valve: If water leaks from the drain valve, it may not have been closed properly. Tighten the valve and ensure it is completely sealed.

By following these steps and maintaining regular maintenance, your water heater will continue to run efficiently, providing your home with reliable hot water while extending the unit’s life.