To flush a water heater, follow these key steps:
- Turn Off the Power or Gas Supply
- For electric water heaters, turn off the power at the breaker box.
- For gas water heaters, turn off the gas supply valve near the thermostat or set the thermostat to "Pilot" or "Off" to prevent heating during the flush
- Turn Off the Cold Water Supply
Locate the cold water valve at the top of the water heater and turn it off to stop water from entering the tank
- Open a Hot Water Faucet
Turn on a hot water faucet in your home (sink or tub) to allow air into the system, which helps the tank drain properly and prevents vacuum formation
- Attach a Garden Hose to the Drain Valve
Connect a garden hose to the drain valve at the bottom of the water heater and route the other end to a safe drainage location such as a floor drain, outside, or a large bucket
- Open the Drain Valve and Drain the Tank
Open the drain valve (may require a flathead screwdriver) and allow the water to drain completely. Be cautious as the water may be hot
- Flush the Tank
After draining, turn on the cold water supply briefly to flush out any remaining sediment. Let the water run through the hose until it runs clear, indicating sediment has been cleared
- Close the Drain Valve and Refill the Tank
Close the drain valve, disconnect the hose, and turn the cold water supply back on to refill the tank. Keep the hot water faucet open until water flows smoothly without air sputtering, then close it
- Restore Power or Gas
Turn the power back on at the breaker for electric heaters or turn the gas supply back on and relight the pilot if necessary for gas heaters
Flushing your water heater regularly helps remove sediment buildup, improving efficiency and extending the heater’s lifespan
. This process typically takes under two hours and requires basic tools like a garden hose, screwdriver, and possibly a bucket
. For tankless water heaters, the flushing process is different and may require vinegar or a specialized cleaner and sometimes a submersible pump; professional help is recommended if unsure
