Trying to replace this leaking heater with a tankless, please help.

[JG plumbing]

You can cap them if they aren't hooked up to your plumbing sytem. Just don't leave "dead legs" especially on the hot side of your system.

 

[sarg]

I suspect we are doomed .... I've had washing machine lines that have been "dead-ends" since the eighties ..... never installed a washer because of a weak well.

 

[JG plumbing]

I suspect we are doomed .... I've had washing machine lines that have been "dead-ends" since the eighties ..... never installed a washer because of a weak well.

What do you think that means? That's like saying "you shouldn't look both ways before you cross the street becuse I did it and I'm fine."

It doesn't really have anything to to with anything.

 

[JG plumbing]

Better yet. When someone asks for professional advise on street crossing, tell them not to look.

 

[Twowaxhack]

What do you think that means? That's like saying "you shouldn't look both ways before you cross the street becuse I did it and I'm fine."

It doesn't really have anything to to with anything.

I think it means a lot. How many people have bathrooms they never use ? And so what if they did use them once in a while ? What’s that going to do when the water is 120 degrees ?


Do you realize 120 degree water actually promotes Bacteria growth ?

I have an office bathroom shower that I haven’t used in a year......20 runs of pipe to it. I have the drain taped off.

 

[sarg]

It means just what I said ..... I suspect we are doomed.
Good news is I'm at the end of the rainbow anyway.
I remember my Dad saying decades ago .... "If you live long enough cancer will kill you."

 

[JG plumbing]

That's why re-circ line are to be circulated at 140° or above.

I'm sure all kinds of people have bathrooms they don't use.

I don't have the chart handy, but you can see why it's a problem in some situations and not others. Temp has a lot to do with it. I'll share later.

Either way you can't say there's no risk, which is why there are standards. There is way to know how many people get sick from their water, the data is not available. Why would anyone assume they people aren't having things happen to them that shouldn't happen with proper plumbing practices, since they don't really know?

 

[JG plumbing]

I agree, if crossing the street doesn't get you cancer will. Almost 100 percent of men over 80 have prostate cancer. Most don't get treatment becuse it's so slow growing it would do more harm than good to get rid of it.

 

[Twowaxhack]

That's why re-circ line are to be circulated at 140° or above.

I'm sure all kinds of people have bathrooms they don't use.

I don't have the chart handy, but you can see why it's a problem in some situations and not others. Temp has a lot to do with it. I'll share later.

Either way you can't say there's no risk, which is why there are standards. There is way to know how many people get sick from their water, the data is not available. Why would anyone assume they people aren't having things happen to them that shouldn't happen with proper plumbing practices, since they don't really know?

That is absolutely incorrect. Circulating water at 140 and above causes mineral precipitation. And is NOT recommended.


Do your research.

 

[Twowaxhack]

Wow this escalated quickly! I haven't capped them yet, that was my weekend project. I guess I'll leave it as is

Which should tell @JG plumbing that there is no dead leg, he’s worried about you.....

 

[JG plumbing]

I'm building spec projects all of the time now with 140 recirc lines. You can tell the engineers and the text books they are wrong if you want the that's what they are.

 

[havasu]

When Navien techs came to help install my tankless WH, it was their recommendation to set the recirculation system at 130 degrees. Any more and you incur unneeded wear and tear on the system, and the gas costs would really hit you hard.

 

[JG plumbing]

Navien is a good brand. They are going to tell you how to make their product last. I have no doubt they told you that.

Also I'm aware of mineralization. It's a matter of prioritization.

I myself at my house use gravity recirc (illegal) and stay about 130.

 

[Twowaxhack]

I'm building spec projects all of the time now with 140 recirc lines. You can tell the engineers and the text books they are wrong if you want the that's what they are.

So you go to customers homes and because they have a circ system you crank their water heater up to 140 ?

You realize that sounds stupid right ?


Do you realize that not all Circ pumps run continuously? Some run on a push button switch.....

What’s the hottest water allowed to be delivered to a lavatory faucet in a residential home ?

 

[Twowaxhack]

Navien is a good brand. They are going to tell you how to make their product last. I have no doubt they told you that.

Also I'm aware of mineralization. It's a matter of prioritization.

I myself at my house use gravity recirc (illegal) and stay about 130.

Exactly, it’s a matter of prioritization....

You’re going to burn more people than you’ll save from Legionella.

If you can post factual information that says different please do.

I can post page after page of people being burned by hot water.

 

[JG plumbing]

I'm not a service plumber.

140 should not go to any outlet only circulate in the pipes.

This is a conundrum. The code hasn't addressed it yet. Mainly because of your concerns and others. But the science I've seen backs what I'm saying and I've built new public buildings to these specs.

I asked similar questions. But here's how it should go. Water heater 140 water leaves, mixes down to 120 max. Water is either used or recirulates and heats back up to 140. Or you can mix at point of use.

 

[Twowaxhack]

Lawyers have addressed it. You set water temp at 140 and someone gets burned, you’re responsible.
That’s not me just talking, that’s fact.

They would literally laugh at you if you claimed it was to kill legionella. Most healthy people are immune to it anyway.

 

[JG plumbing]

How are you burning someone with mixed water?

 

[JG plumbing]

It's actually not as mind-boggling as you think how do you think people heat water with their boilers?

 

[Twowaxhack]

How are you burning someone with mixed water?

How are you limiting hot water all over a home while circulating it ? It’s not practical, it’s kinda ridiculous. Most faucets do not have internal ways to limit hot water.