Hot water heater problem - need advice

[samclem]

Quote:

Originally Posted by Winemaker Agree on most of the points above, however, with some older installations, a 175 psi pressure relief valve was common. Today, codes require 150 psi, hence the use of the expansion tank.

I'm pretty sure the primary reason for expansion tanks is the installation of backflow prevention valves in public water lines. Before the codes changed and these backflow valves became common, there was no need for an expansion tank because any increase in pressure due to the heated water in the WH could simply flow back into the water mains. But if the water can't go backward, then an expansion tank must be fitted to prevent possible damage to the household pipes.

[travelover]

My TP valve failed and got the basement carpet wet. I replaced the TP valve and it was fine after that for years, maybe still is (I've since sold the house). The previous water heater lasted over 20 years. I replaced it just as a precaution.

[mountainsoft]

Quote:

Originally Posted by travelover My TP valve failed and got the basement carpet wet.

My TP valve is piped to outside the building. I think that's code now? If it leaks or is triggered by temperature or pressure the water all goes outside.

I also have a drain pan that drains outside, so a "slow" leak shouldn't cause problems either.

However, I did have a fitting fail on the flexible supply line at the top of the water heater. I was so lucky to have caught it leaking when it was just a tiny drip. I turned off the water and grabbed the pipe and it broke off in my hand. I'm so thankful it didn't fail while I was away from home spraying full water pressure all over the laundry room.

[Winemaker]

Quote:

Originally Posted by samclem I'm pretty sure the primary reason for expansion tanks is the installation of backflow prevention valves in public water lines. Before the codes changed and these backflow valves became common, there was no need for an expansion tank because any increase in pressure due to the heated water in the WH could simply flow back into the water mains. But if the water can't go backward, then an expansion tank must be fitted to prevent possible damage to the household pipes.

Backflow preventers have been required in my area since the '70's. However, hot water tanks specs for strength declined since then and the 175 psi T and P valves were eliminated, and replaced with 150 psi.

I do the plumbing work for my 4 rentals and my mom, brother and sisters. All have backflow preventers that were installed when the houses were built, and I have been forced to install the d@#n expansion tank after replacing their water heaters.

[Car-Guy]

I posted this before, so I just cut and pasted what I have already posted below in the blue text. FWIW. If you don't already have an expansion tank, it may be worth considering.
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I'm sure I've posted this here before (well maybe) but a just a few words about water heater expansion tanks since it may help someone.

A few years ago, my "problem free" ~8 year old water heater started dripping out of the T&P valve. (not a good sign). So I replaced the T&P valve, several times. It always started leaking again within a 15 minutes . Checked the water pressure on the incoming line and it was well over 100psi (WTF). So I installed a pressure regulator valve and cut the in coming pressure down to about 70 psi (which is actually still pretty high) The T&P valve still dripped. Ok, bit the bullet and replaced the water heater. Guess what, the new water heater started dripping out of the T&P valve too within 15 minutes. Ok, time to read the instructions and on line info. After reading more than I ever wanted to about water heaters, I discovered what an expansion tank does. Hum, ok, sounds like it's worth a try. Less than $100 and 45 mins of work and it was installed. Fixed the dripping problem!

Apparently, the local water company had recently increased the water pressure on our community water system and installed checked valves but they never said anything to the customer base...

[48Fire]

Quote:

Originally Posted by RAE I have a 40-gallon gas hot water heater in the (unfinished) basement, that has operated flawlessly for 16 years, until yesterday. So..........what would you do? I guess after 16 years, I should probably be thinking about just getting a new heater, but something tells me that the problem is just with the relief valve, and maybe all that needs to be done is to replace it, to get a few more years out of this unit(?). I hate to replace the whole unit if a $20 fix would work for now. Would you attempt to replace the relief valve yourself, or is that something best left to a plumber? If it is the latter, that might push the decision toward just getting a whole new unit installed, I suppose. Any advice would be appreciated.......thanks.

Not a chance I would put any money, time, or energy into a 16 year old hot water heater.

I am calling on replacing ours tomorrow. It was manufactured in 2003, not sure what year it was installed, but I am guessing within a couple years of that. It works fine, but I like updating my hot water heaters proactively, and avoiding a disaster and an unhappy wife

[ERD50]

Quote:

Originally Posted by homestead FYI: That leak could be caused by a faulty expansion tank. You can check the pressure on the tank. If water comes comes out when you test it, then replace it.

Agreed. And I've known of several water heaters (mine included - a basic 6 year warranty type) that worked just fine at 30 years age. A lot depends on the water quality. As others have mentioned, if you have a backflow preventer (check valve) at the connection to the municipal supply (code in most areas now), when the water is heated, it expands and has no place to go - that is why you need an expansion tank. If the expansion tank is full of water, no air space, the pressure increase will trip the release valve.


With some expansion tanks (the ones w/o a bladder/diaphragm), you can just drain the water out, and (I think) pressurize the tank again. That type tends to get 'water-logged', as the air is absorbed by water over time.

Quote:

Originally Posted by jazz4cash My experience is that the life of a water heater (don't wanna be chastised for calling it a HWH) ...

Thank you for that!

-ERD50

[John Galt III]

Quote:

Originally Posted by mountainsoft However, I did have a fitting fail on the flexible supply line at the top of the water heater. I was so lucky to have caught it leaking when it was just a tiny drip. I turned off the water and grabbed the pipe and it broke off in my hand. I'm so thankful it didn't fail while I was away from home spraying full water pressure all over the laundry room.

Mountainsoft, that wasn't a Sharkbite, was it ? Was it the flexible hose that failed or the fitting it was screwed onto? I have Sharkbite hoses on my WH, that's why I'm asking. Thanks

[mountainsoft]

Quote:

Originally Posted by John Galt III that wasn't a Sharkbite, was it ? Was it the flexible hose that failed or the fitting it was screwed onto?

No Sharkbite, it was a typical braided stainless hose similar to this one (I think we had Watts brand) https://www.homedepot.com/p/Fluidmaster-18-in-Water-Heater-Connector-B1H18/20376397

The hose part was fine, but the fittings on the ends started corroding and eventually the fitting completely separated into two pieces. The second hose on my heater was still intact but I could see signs of corrosion on it too. There wasn't any corrosion where it screwed onto the water heater, just within the two pieces of the fittings themselves.

Ironically, I had used the same type of hose at my in-laws house several years ago. So I checked theirs and saw signs of corrosion and minor leakage at the same point. Yikes. In all cases the hoses were fine, it was the fittings that were falling apart. Thankfully I caught the issues with the hoses before they broke and flooded the house.

I replaced the hoses on both water heaters with a corrugated type stainless steel hose like this https://www.lowes.com/pd/Apollo-Stainless-Steel-Water-Heater-Connector/999927070.

These don't have the swivel fitting like the braided hoses, just a nut that clamps the flared end to the pipe nipples on the water heater. They are a bit harder to find around here, but hopefully they will be more reliable in the long run.

The scary thing is those stainless braided hoses are the standard hose (in smaller 3/8" sizes) for connecting sinks, toilets, washing machines, etc. That's all they sell around here and we must have a dozen of them in our house. I hope they hold up better than the water heater hoses did.

FYI: I did a quick Google search for braided water heater hose failure and found this site mentioning the exact same problem (with photos). Sounds like a common problem. Water Heater Hose Failure – WATT Stainless Steel Hose « remodeling for geeks

[48Fire]

Had our new water heater installed yesterday. It was 15 years old, and we didn't want any disasters. The plumber fixed a few connections that were failing as well. Plus, brought a few things up to code.

[MoneyIsMyHobby]

Quote:

Originally Posted by mountainsoft Unfortunately, our 80 gallon tank is going to be hard to replace. It fits in a small alcove in our laundry room, and thanks to new energy requirements the new 80 gallon tanks are larger and won't fit in the space. So we'll probably have to downsize to a 50 gallon just so it will fit and hope it can put out enough hot water to fill our large bathtub. I would switch to a heat pump water heater, but again because of where it's located it would not work very well.

What about an instant/tankless WH if space is your concern plus enough HW to fill the tub?

https://www.homedepot.com/p/Westinghouse-11-GPM-High-Efficiency-Natural-Gas-Tankless-Water-Heater-with-Built-in-Recirculation-and-Pump-WGRGHNG199/300358962?cm_mmc=Shopping%7CG%7CVF%7CD26P%7C26-10_WATER_HEATERS%7CNA%7CPLA%7c71700000033150351%7c 58700003868932468%7c92700031086622955&gclid=Cj0KCQ jw0PTXBRCGARIsAKNYfG0lV0PGXT5PcR6QlOVXjCF7l3b0Gf OXzeKQuL8KM5tEq3SJKAbTIaAgJiEALw_wcB&dclid=CJWBup_ 1jNsCFUHawAodyQYECA

[mountainsoft]

Quote:

What about an instant/tankless WH if space is your concern plus enough HW to fill the tub?

We don't have gas here, electric only. I looked into tankless electric when we built our house but it wasn't a viable option for us. The size needed to heat our cold well water would overwhelm our electrical service.

A standard tank model is still our best option. It's just a shame they don't make a slightly smaller 70 gallon tank with the same outside dimensions as our current 80 gallon tank. These days the largest size I've been able to find that will fit is only 55 gallons.