How to Drain a Water Heater

Draining your water heater once a year removes sediment from the tank that can cause it to work harder and cost more to use.

The No. 1 cause of water heater failure is sediment buildup in the tank. Sometimes it makes a sizzling, crackling noise when the heating element fires up as it works harder to heat the water. This wastes energy and often requires earlier replacement.

However, you can save money and extend the life of your water heater by draining your tank and flushing away sediment at least once a year.

Flushing a water heater every year can remove a build-up of sediment from the bottom of the tank. That sediment can create a buildup on your water heater’s elements and make it harder for your water to get hot.

Here’s how to go about it:

  • Turn off the gas or electricity to the water heater.
  • Close the cold water supply valve coming into the water heater.
  • Attach a garden hose to the drain at the bottom of the tank.
  • Run the hose outside on the ground.
  • Open the drain valve on the tank.
  • Release the pressure relief valve on top of the tank.
  • Allow the water in the tank to drain out.
  • Once the tank has drained, open the cold water supply valve for a few minutes to flush out any sediment.
  • Close the drain valve and pressure relief valve.
  • Remove the hose from the drain valve.
  • Allow the tank to fill.
  • Turn the power back on or relight the pilot light.

Before sure to also check your thermostat. It should be set at 120°F or lower. A water heater that might have lasted only 10 years could now last 15 or 20 years, or even more.

For more information, see our video on Water Heater Maintenance.

Further Reading


  1. You glossed over a very important point: for those with gas hot water heaters, you say “turn the gas off.” Is there a special gas turn off on the hot water heater, or do you mean turn the gas off at the house, which is a big deal. The utility company doesn’t want us to turn off the gas to the house, unless really necessary. Please clarify.


    • Hi Andy,
      When draining a hot water heater, turn the gas off at the heater, not the main for the whole house, by turning the control knob on the water heater to “off.” Or you can turn the water heater to “pilot” while you’re draining it, that way you won’t have to relight the pilot light when you’re done. Same applies for the power on electric water heaters, turn the breaker to the heater off, not the main breaker for the house. The purpose is to keep the gas burner or electrical elements from cutting on while the heater is empty.

    • Sorry Andy, Don’t mean to be anyway, except straight-up. I did not see ANY
      “glossing-over” of anything. I’m a 55-year-old divorced woman who doesn’t know a whole lot about maintenance/plumbing but I know a tad bit and the instructions were very to the point to say the least.
      -they said “turn off the gas TO THE WATER HEATER”.I don’t think they could be any more explanatory than that. Js.
      Note: I also firmly believe if they meant the “main valve” they wld have definitely said that :):);)

  2. Dear Danny Lipford,
    Any suggestions on how to drain the hot water heater when it is in the basement below grade (not a walk out)?
    Johnnie stewart

    • Hi Johnnie,
      If you have a drain in your basement floor or a bathroom in the basement, you could drain the water heater into it. Otherwise, you would have to let the water in the heater cool, then full buckets and carry it out. Good luck with your project!

  3. Dear Danny Lipford,

    My hot water heater is attached to my oil burner. Is there a similar switch that I should turn off before emptying my hot water heater? Thanks.

    • Hi Karen,
      I’m not familiar with that type of set up, but in any case, I would put your oil burner on pilot or standby when draining your water heater to keep it from heating up while the water heater is empty. Good luck with your project!

  4. I am not sure if this is normal but my hot water heater which is gas drains constantly, the water heater is outside under the house so it drains into the yard. is this normal my contractor who installed it says it is but i am not so sure.

    • Hi Mia,
      I’ve never heard of a hot water heater that drains constantly being normal. It should be a closed loop that only drains when you open the valve or if the pressure builds up too much and causes the pressure relief valve to open. It sounds like either the drain valve or the pressure relief valve are leaking and one or the other probably needs to be replaced. To find out how to replace a pressure relief valve, check out our article How to Repair a Leaking Water Heater Pressure Relief Valve. Good luck!

  5. Thank you so much for your info on draining and re seating my pressure valve you may have just saved us another $500.

  6. Danny,

    Your site says to never drain water when it is hot. We have an electic water heater. Do you just turn it off and wait for the water to cool down? If so, how long?

    • Hi Steve,
      The reason you should cool the hot water in the tank down before draining is that garden hoses are not usually designed for very hot water. Also, hot water can kill plants or grass in your yard. Just turn of the power to the water heater, then run the hot water in the house (or take a shower) until it cools down some before draining the water heater. Good luck with your project!

  7. i bought a new elec water heater and replaced the plastic drain valve with a brass one when i installed it. i put a hose on the valve and turned the knob but no water will come out of the tank. not even a drop. i thought i was doing right since my old heater with a plastic valve leaked all the time . got any ideas.

  8. I am having no luck draining a hot water tank at a camp, that pulls from a very hard, sediment prone water supply. I drain the tank every year for the winter, but this year nothing will drain out. Do you think there a lot of sediment buildup? How do I drain the tank that is totally blocked? Can I feed a coathanger thru the valve to clear a way? I am afraid I will ruin the valve and not be able to stop the flow onto the floor if it should free up. Thanks.

  9. Is there an inexpensive pump available that could pull the water from my basement water heater (once cooled) through a window approximately 4 ft. higher? I don’t have a drain or other option in the basement.

  10. You really don’t need to turn the gas off. Just turn it ti pilot and wait a few hours and the water will be cool. Next, use a bucket and fill it from the drain valve and dump it in the floor drain or wash tub. Do this for half the capacity of the tank. Do this once a year and your water heater will last indefinitely. Mine is on its 22nd year.

  11. My hot water heater is 16 years old and has never been drained. Is it prudent to drain it at this point? Am I living on borrowed time?

  12. My water heater is electric and it will produce hot water for a while then the breaker pops off and I have to go down and flip the switch to get hot water again. Can a bad element cause this to happen? thanks

  13. Have you ever heard of someone feeding the cold water to the drain input (with appropriate connections added for draining) and plugging the old cold water feed on a residential water heater?

    It is frustrating to not be able to find a dip tube for a GE heater.

  14. We cannot get the hose on our water heater. There is no room, the cold pex line is right in the way. Do we, plumber, have to unhook the cold brass line from the pex cold line there, just to get some room for hose adapter, to drain it? And the drain valve is plastic, so very carefully. We live in mobile home, no room for blunders, from any plumber. It looks like to me this is the only way, cause not even 2 strong guys, will be able to move this, approx. 1 inch to the right, with 40 gal. of water in it, just to get the hose on?

    • Hi, Robert,
      Here’s “Today’s Homeowner” host Danny Lipford’s answer to your question:
      “It is possible that your drain spout is not releasing the water, but more commonly, it’s the pressure relief valve that has to be released to prevent a vacuum stop of the water.”
      Thanks for your question.

    • Hi, John T.,
      Here’s “Today’s Homeowner” host Danny Lipford’s answer to your question:

      “Most likely, the aerator that is attached to the end of the faucet spout may have gotten clogged. Simply unscrew, soak in vinegar and reinstall after 30 minutes or so, and you should be fine.”

      Thanks for writing to us!

  15. Hi, I am in the process of replacing my hot water heater; the supply line is shut off but I have water feeding back into the heater from the hot water outlet line. Is this normal? I thought it might be from the hot water lines in the house but it’s been draining for several hours.

  16. A tip if your pressure relief valve is on the side of your tank, like mine.
    Don’t open it to break the vacuum–water will drain from it until the level is below the valve. Instead, simply open one of your hot water faucets inside the house.

  17. I have an electric water heater and no water comes out from the drain valve when I follow the steps.
    I tried turning the cold water supply on, and then the water started coming out of the drain valve.
    I turned off the cold water supply valve again and tried again but no water comes out.

    I don’t think the valve is clogged because water comes out when the cold water supply valve is on, so I’m very confused what’s the problem.
    If anyone has any insight, that would be appreciated.

  18. if you discharge the water in the Water Heater tank, how many is the maximum days for it to re install? because we need to renovate a room and need to remove the water heater.

    • Hi, John,
      We don’t see why a properly drained water heater couldn’t be allowed to sit empty as long as needed.
      But there are different types of water heaters and tanks, so we recommend contacting the appliance’s manufacturer or a plumber for an opinion based on your specific equipment.
      Good luck!

  19. Can I drain a hot water heater by turning off the cold water and turning on a faucet instead of hooking a hose to the drain valve?

  20. Question; how to drain 1 gal of water from a gas water heater. My plumber said to open the hot water above the tank and then drain it into a large pail once a month. He said don’t shut off gas or power. What do you think? Also to open the valve, use a screwdriver and turn? counter clockwise?

  21. I followed these directions and I went to use the hot water from kitchen faucet and it sputtered for a good while. Is this normal after draining the water heater? Similar sputtering at other faucets.

  22. I did the draining procedure like it says but when i turn the cold water valve off the water stops coming out what am i doing wrong?

    • Hi, Jerry,
      Unfortunately, there’s no way of knowing what could cause this problem without a house call. (There could be any number of reasons.)
      We recommend contacting a plumber for the best advice.
      Good luck!


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