Tools You'll Need
Step-by-Step
Turn off the power or gas
Electric: turn off the breaker. Gas: turn the gas valve to 'Pilot' or 'Off'. Never drain a water heater while the power or gas is on — the empty tank can overheat.
Connect a garden hose
Connect a garden hose to the drain valve at the bottom of the tank. Run the other end to a floor drain, outside, or a bucket.
Open a hot faucet
Open a hot water faucet somewhere in the house. This lets air into the tank so it can drain.
Open the drain valve
Open the drain valve slowly. Water will flow out. CAUTION: water is hot. Let it run until the water runs clear — this may take 10–20 minutes.
Close and refill
Close the drain valve. Remove the hose. Open the cold water supply. Let the tank fill — you'll hear water running. When water flows steadily from the open hot faucet, the tank is full. Close the faucet.
Restore power or gas
Electric: turn the breaker back on. Gas: relight the pilot or turn the gas valve back on per the manufacturer's instructions. Do NOT turn on power/gas to an empty tank.
WHEN TO STOP
- If the water coming out is rusty or has a lot of sediment, the tank may be corroding — flushing may not help long.
- If the drain valve won't open or is clogged, don't force it.
- If you smell gas at any point, stop and leave the area.
- If the water is too hot to handle safely, wait for it to cool first.
WHEN TO CALL A PROFESSIONAL
- The tank is 10+ years old and hasn't been flushed — sediment may be hardened and flushing may not help.
- The drain valve is clogged or won't open.
- You're not comfortable working with hot water or gas appliances.
- Rusty water comes out — the tank may be corroding and need replacement.