Hot water heater leak

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msherer

Burning Hunk
Dec 9, 2010
109
IL
My hot water heater started randomly leaking around the pressure relief valve located on top of the heater. The leak is coming from where the valve goes into the heater. Is this something that can be repaired or am I looking at a new unit?

Matt
 
How old is the unit? Is the unit out of warrenty? If it's old and out of warranty be proactive and swap it out.

Can you see the actual leak or just were the water is appearing from the outer case?
 
Are you SURE it's the threads leaking? Or perhaps water from the valve opening dripping down? It's rare for the threads to leak. If so, you could carefully try tightening the valve into the tank, but that could result in a mess.
 
I guess I can't be 100% sure but I put my finger around the inside of the valve and it was dry. Pooling up around the base. Unit is 5 years old. I'm not gonna touch it without draining it first. Replacing it might be the best route.
 
Yep your right around the end of any warranty- guaranteed to self destruct at that point- planned obsolescence.
 
As long as its not the tank itself leaking, replace the offending part and move on. The parts are relatively inexpensive and the effort is much less than replacing the whole unit. I've had units last over 30 years as long as they're flushed every few years, and the sacrificial anode is replaced when it wears out.
 
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Exactly. Drain. New relief valve, Teflon tape (& pipe dope for me personally) tighten and done. No need to needlessly replace. Everyone's to easy to throw out things that can be easily fixed in this disposable society we live in these days.
 
And if that doesn't fix it it's not like your out a ton of money, relief valves are cheap.
 
While you are at it, figure out where the anode is and inspect it. It usually looks like a big threaded plug on the top of the tank. If you have aggressive water it could be eaten already. A hot water heater will last for a long time as long as its gets the sludge drained out of the bottom once a year and the anode kept in good condition. Anodes are cheap, the hassle usually is that the heater is too tall to pull the anode without hitting the ceiling. You can buy flexible replacement anodes on line (the look like string of hotdogs). All you do is pull the old one out and cut it if you need to then slide the new one in. Apparently a lot of anodes got sourced out of china and the Chinese anodes aren't holding up. A bad anode will look like its corroded and if it gets bad enough the bottom will be corroded away.
 
No need to drain the whole tank to replace the relief valve either.
Just shut off the supply valve, drain the water down enough so that water doesn't leak out, replace the part and so on.

I've found this site to be a good basic reference for this sort of thing.
http://www.waterheaterrescue.com/
 
Just a warning that depending on age of heater and water quality you may not be able to unscrew the T&P vale or anode. I have had several big men, cheater bars, and impact wrenches that haven't touched them. Ended up just installing new unit.
 
Yeah, these things are cheap and failure of the tank can be catastrophic in terms of damage to the home. They are very easy to replace and come with a brand new anode rod and TP valve so you save all the hassle of replacing it.

I don't even drain the sludge out. You're just increasing the chances of getting a leaky drain valve.
 
If you are on city/town water supply without a domestic expansion tank (ie Therm-x-trol st-12) you could be getting expansion as the tank heats up, but this will usually leak out the drop tube near the floor not the threaded bung. As many have said get a new watts xl 100 and drain tank, inspect the bung for pitting and leaks then install new relief valve and be known your way. Ifor you have a domestic expansion tank it would be a good idea to replace that also. All parts should be under $100
 
I don't even drain the sludge out. You're just increasing the chances of getting a leaky drain valve.
I replace the original (usually plastic) drain valve with a full flow 1/4 turn brass unit that allows me to drain the minerals/sediment more quickly with less clogging.
 
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I replace the original (usually plastic) drain valve with a full flow 1/4 turn brass unit that allows me to drain the minerals/sediment more quickly with less clogging.

I thought about doing that when I replaced my current water heater. The brass valves are sold right there next to the heaters. I didn't want to mess with the seal or introduce another DIY leak. Plus, with the required drain pan under the tank, the brass valve would stick out really far.

Also, I read that there is a liability issue in doing this since some little kid could walk up and open that valve and be doused with hot water.
 
Also, I read that there is a liability issue in doing this since some little kid could walk up and open that valve and be doused with hot water.
Hadn't thought of that. I always put a hose cap on mine just in case so I'm assuming that would protect against knocking it open.

Added point. So much mineral sediment builds up in ours that I have to insert an auger drill though this drain to break the stuff up and get it to flow out.
 
Hadn't thought of that. I always put a hose cap on mine just in case so I'm assuming that would protect against knocking it open.

Added point. So much mineral sediment builds up in ours that I have to insert an auger drill though this drain to break the stuff up and get it to flow out.

Yes, a cap is a great idea to prevent against a leaky valve in the future or an unplanned opening. You can probably also remove the valve handle too.

We are lucky to have naturally soft water but with iron/manganese and grit from the well. I have an iron filter with a cleanable screen ahead of it so the water heater shouldn't see much sludge accumulation. I hope. I expect the sludge will accumulate at a rate so slow that the heater will be out of service before it hits the bottom element.
 
Good idea on removing the handle - easy enough to do.
We have a fairly nice water filtration system (sediment & activated carbon) but of course that does nothing for dissolved minerals (hardness).
Its interesting that our water heaters basically soften our DHW. I have to remove the minerals from the tanks every 2 years or it builds up the height of the first heating element and kills. it.
 
My goodness you guys must be retired with all of those solid, good ideas!

If I were to fix a leak I would do a new brass drain, new anode, but the water cap that's almost over the top lol. But still a great idea... ==c
 
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