I flushed my hot water heater several months ago. Ever since, it has leaked through the drainage spigot.

I've tried to tighten it to a point where it looks like it stops, but it starts again soon after.

Is this something that is easily replaced, or any actions I can take to stop it from leaking?

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I was able to drain the heater, and remove the drain plug. It has a washer that had worn out. I just replaced the entire plug with a new one.

Thank you everyone for the assistance.

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    I have replaced several , you will need to turn off the water and power and drain the heater, I find opening the T&P valve allows it to drain faster. Use caution when unscrewing it from the tank , I have found both 1/2” and 3/4 valves and usually use brass valves and nipples with pfte tape. – Ed Beal Jan 29 '20 at 7:00
  • Ed Beal, thanks for the information. Any tips on unscrewing the old one? I'm worried I'll damage the heater itself when doing this. – AaronS Jan 29 '20 at 15:29
  • Great update. Thanks for the images ! – Fresh Codemonger Feb 3 '20 at 7:29

Those plastic shut off valves on water heater tanks are obviously very cheap and probably low quality as well.

There are likely two main reasons that the valve leaks (maybe three).

  1. There could possibly be residual grit and particulate laying in the valve assembly that keep it from seating correctly. If you captured the initial flush water from your tank in a bucket you would no doubt see some of the sediment in the bottom of the bucket. Sediment build up does happen to accumulate on the inside of the valve due to the small pocket that the attachment point creates inside the tank.
  2. The valve parts could be getting old and corroded to the point that the valve cannot seal fully against the valve seat.

Mitigation information:

  1. If you have a sediment problem you can try to open and close the valve multiple times to try to get the sediment to wash out.
  2. It may be necessary to replace the valve. There are available online videos that can walk you through a valve replacement so I will not cover that here. The main recommendation however is to replace the valve with a nice quality ball valve.
  3. Depending upon the type of valve seats that are in your valve it is possible that it could have seen some damage due to applying too much closing torque to the valve. If this is the case replacement is the best course of action.
  • Thank you for the detailed information. If I want to replace this, I'm assuming I need to replace the entire fitting, and not just the cap, correct? I was able to find a few youtube videos on this, I'm just a little scared I'll break the entire heater when doing this. Also, does this look like the proper replacement for it? homedepot.com/p/… – AaronS Jan 29 '20 at 15:21
  • @AaronS - The valve you show from the from the 'Depot is one style that will fit a good number of water heaters. It may or may not fit yours. Best advice is to remove yours and take it along to the store when you go to buy the replacement. This way you can be assured to get something that will work. I still recommend to get a large diameter quarter turn ball valve with nice lever handle instead of something like you picture linked. The ball valve may require additional fittings and adapters to fit up to your water heater. – Michael Karas Jan 30 '20 at 4:24
  • Thank you again. I was able to replace the drain. I added more images of the damaged plug and the new one in the original post. – AaronS Feb 2 '20 at 2:26

I had this problem.

I created a short connector using a brass garden hose thread to female iron pipe thread, a male iron pipe thread to pex connector, a short length of 1/2" pex and a 1/2" sharkbite end plug. While the drain assembly continued to leak it leaks into this short length of pipe and fills it.

If I ever drain it I can just unscrew the connector assembly. I've had this solution in place for 9 years. I made the 1/2" pex with plug shorter later - this was just the only pic I had handy. Even with the connector slightly bumped as in the picture it still sealed the leak.

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  • Thanks for the information. I thought about doing something similar and just routing it to one of the drains in my basement. However, I'm selling the house soon, and I don't think the inspector is going to like that. – AaronS Jan 29 '20 at 15:28
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    They don’t like plumbing on them but it is legal. With the ones that had a metal nipple I used a torch to heat the nipple to soften the pipe dope once it was hot it came out easily. I was afraid of breaking things before heating it did not want to turn. – Ed Beal Jan 29 '20 at 17:53
  • Great thank you. – AaronS Jan 29 '20 at 18:57
  • @AaronS your tank looks bad already - like mine - with the scorching. Home Inspector will likely write it up as needs replacing in either case. – Fresh Codemonger Jan 29 '20 at 18:59
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    @FreshCodemonger - If I were you I would strive to move the combustible material away from the water heater. You have a cardboard box that appears to be labeled with a SIEMENS logo butted right up against the heater. This is limiting air circulation around your water heater and can lead to additional heat buildup around the unit. Move that box out of there. – Michael Karas Jan 30 '20 at 4:29

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