Leak from threads on TPR fitting

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*Edit: I'm not sure the leak is coming from the threads. I got another photo up close of what appears to be condensation on the sleeve that surrounds the valve.

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15 year old tank with no issues until this morning. Found slow drip coming from threads on the TPR valve. Water is somewhat hard here, so it's going through a softener (installed 3 years ago). Is it not worth the energy and time trying to replace the TPR?

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WorthFlorida

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That leak is probably from the threaded nut welded to the steel water tank. The leak can actually be anywhere on above the valve. Most WH's will leak is at any welded joint. When hot water is running the pressure drops and when the water is heated it expands. The pressures can get quite high, well over 100 PSI. Be sure to install an expansion tank, required by the manufactures and some jurisdictions.
 

Reach4

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I should add that it doesn't seem to leak when the hot water isn't running.
That is odd. I cannot think of a problem that could cause that symptom.
Is it not worth the energy and time trying to replace the TPR?
It's not a lot of energy and time, but with that other observation, this leak does not seem to be one that replacing that valve would solve.
 
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That leak is probably from the threaded nut welded to the steel water tank. The leak can actually be anywhere on above the valve. Most WH's will leak is at any welded joint. When hot water is running the pressure drops and when the water is heated it expands. The pressures can get quite high, well over 100 PSI. Be sure to install an expansion tank, required by the manufactures and some jurisdictions.
This would explain why it's only leaking during the heating process... I'm guessing I shouldn't even bother pulling the valve off to replace it?
 
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Leak is getting worse by the hour. Now constant dripping with or without hot water running. Is tankless worth the extra $$ if you might move in less than 10 years?
 

jadnashua

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The further north in the US you go, the less likely a tankless will work well for you. They're specified output is based on the incoming water being 50-degrees or higher...in Michigan, I'd bet it gets closer to freezing after a cold spell. That could be nearly 20-degrees cooler output at full tilt. Probably work fine for smaller draws. Plus, you might need to redo your gas meter and supply lines, possibly all the way to the street, depending on what you have now, and that can get quite expensive not counting the fact the units cost more than a tank by a fair amount you'd never recoup in energy savings for the most part. When you need to repair it, not everyone will have the parts or the moxy to know how to fix it, either.
 
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I would replace with a tank. The expense of going with tankless would never be recovered in that amount of time.
Thanks! To swap out our existing 75 gallon with another identical one is $600 less than going with the Navien NPE-240A2. Do you think it still makes sense to stay with the tank in Michigan?

I guess another route is to downsize to a 50 gallon, but I'd be nervous that may not be enough for 5 of us and a jetted tub...
 

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Thanks! To swap out our existing 75 gallon with another identical one is $600 less than going with the Navien NPE-240A2. Do you think it still makes sense to stay with the tank in Michigan?

I guess another route is to downsize to a 50 gallon, but I'd be nervous that may not be enough for 5 of us and a jetted tub...

The Navien puts out 5 gallons a minute in the Northern climates . Not normally recommended for big tubs. It is endless though. And $600 more isn't much. Maybe others will post their thoughts too.
 

Reach4

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You might need to upgrade your gas piping for 199,000 BTU vs about 50,000 for the tank. But you do make good points. If you need a deciding factor, you might ask a local real estate agent if buyers have a preference for tank vs tankless. Let us know what the agent says.
 
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The Navien puts out 5 gallons a minute in the Northern climates . Not normally recommended for big tubs. It is endless though. And $600 more isn't much. Maybe others will post their thoughts too.
Hmm, well I've never run out of hot water with the big tank. I wonder if 5GPM is enough for two showers at the same time.
 
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You might need to upgrade your gas piping for 199,000 BTU vs about 50,000 for the tank. But you do make good points. If you need a deciding factor, you might ask a local real estate agent if buyers have a preference for tank vs tankless. Let us know what the agent says.
My gas pipe entering the house from the meter is 1". The estimate never said anything about that being an issue, but do you think it might be? That would be a headache to get most of the way through the project to find out my supply lines aren't enough, hah.
 

Reach4

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My gas pipe entering the house from the meter is 1".
Does it then expand up for the trip to the furnace?

Gas is usually distributed in a house at about 0.25 psi.

I know they say that proposed tankless can run with 1/2 inch in, but there is going to be a length and elbows limit. I think there are calculators and estimators for figuring the drop for gas pipes.

There are some places that will regulate down to 2 psi at the meter, and then have individual regulators to drop the psi at each appliance. Those can really get a lot of BTUs thru a given size pipe. But most gas companies will not do that. Sure would make it easy to get gas to a whole house generator in the back yard.
 
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Does it then expand up for the trip to the furnace?

Gas is usually distributed in a house at about 0.25 psi.

I know they say that proposed tankless can run with 1/2 inch in, but there is going to be a length and elbows limit. I think there are calculators and estimators for figuring the drop for gas pipes.

There are some places that will regulate down to 2 psi at the meter, and then have individual regulators to drop the psi at each appliance. Those can really get a lot of BTUs thru a given size pipe. But most gas companies will not do that. Sure would make it easy to get gas to a whole house generator in the back yard.
The 1" pipe makes a straight run towards the furnace and water heater. It tees off to 1/2" sections for the furnace and water heater separately, but those are short runs with very few elbows. Not sure if the psi at the meter. Real estate agent says go tankless, several people in the sub have the Navien. Guess that's my answer
 

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Hmm, well I've never run out of hot water with the big tank. I wonder if 5GPM is enough for two showers at the same time.

Shower heads are restricted to 2.5 gallons or less. A tankless at 5.0 gallons a minute at 120 degrees easily runs two showers at once.
You're also mixing down to about 100 degrees.

A tankless will require it's own venting for exhaust, it can't reuse a metal chimney that the old gas tank used.
The new venting is often PVC and for some, stainless steel.
 

Tuttles Revenge

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Curious how a tankless would cost so similar to a like for like installation
Do you know what the gas pipe size is supposed to be at the inlet for the Navien?

The navien is fed from 1/2" pipe up to about 25ft or so but it draws in gas rather than using gas pressure to supply it. It still wants to be fed from a pipe sized to supply 200k btu and generally wants to be the first appliance from the meter.

I would get a second/third opinion on replacement tank vs tankless.
 
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