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

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You need to add these components to the water lines so you can flush the system with vinegar. If you dont ever service it, it will be shorted lived.
note: I have heard the PRV is not necessary on a tankless (would like to hear what the pros here have to say about that), but the other valves are for sure because you have to occasionally flush it out.
You say PRV, but you probably mean T&P. On those tankless bypass service kits, they come with a "pressure relief" valve. It is not a traditional combi one for temperature too, since tankless have temperature controls that are adequate (if you trust the engineers).
 
This is also why every water heater needs a temperature gauge coming out of the TOP nowadays. The thermostat on the bottom of the water heater is not a reliable way to set the temp.
 
Rheem units
This is also why every water heater needs a temperature gauge coming out of the TOP nowadays. The thermostat on the bottom of the water heater is not a reliable way to set the temp.

Yeah, and what would that do for you besides add another part to the system to fail ?

I’m glad you’re not writing the code yet 🤣✌️ But I’m sure you’ll fit right in when you start.
 
You mix at the water heater or you mix at point of use not in the faucet. Under the sink where the hot and cold lines are.
 
The temperature gauge lets you actually know your at 140 not set 140 on the thermostat and have it come out 155
 
You mix at the water heater or you mix at point of use not in the faucet. Under the sink where the hot and cold lines are.

You can’t mix it at the heater if you’re circulating it.

You’re going to install mixing valves under the sinks ? Thermostatic ?

Because our incoming water swings 20 degree from winter to summer.

And that still wouldn’t help infrequently used bathrooms.......just sitting there growing Legionella. Circulating 140 water in a home ....jeezzz brother that’s nuts and doesn’t solve the problem.
 
The temperature gauge lets you actually know your at 140 not set 140 on the thermostat and have it come out 155

Water heater thermostats typically take a 10-15 degree swing to turn on and off. Most electric thermos don’t even have numbers any longer and I don’t believe gas thermo dials ever did.

You going to wait around for the tank to heat up after you install or service a water heater ? I’m not. I set it in the middle and hope for the best, it works for me. Usually that works out to around 120-130.

What would tank temp matter so much you needed a temp gauge ? Why not check temp at the first and last fixture from the heater ?
 
The project I built as the pandemic began with a sheriff's office. The public portion of it had restrooms with 140 degrees circulated water going to them I screamed from the top of my lungs that they needed mixing valves at the lavs, they never listened. The engineer left that part out the only part he got right was 140° circulating water.

We'll see what the lawyers have to say about that one.
 
The project I built as the pandemic began with a sheriff's office. The public portion of it had restrooms with 140 degrees circulated water going to them I screamed from the top of my lungs that they needed mixing valves at the lavs, they never listened. The engineer left that part out the only part he got right was 140° circulating water.

We'll see what the lawyers have to say about that one.

If someone gets burned then everyone will pay except the city inspectors. They have immunity.

There’s no debate there.

Steakhouse here had 150 water going to a handicap lavatory and to top it off the hot snd cold were reversed at the faucet.

Guess what ? Mentally handicap boy got burned. Burned his hands up. They paid fir it too.....
 

Nice huh......but you still haven’t addressed the rarely used bathrooms.

The Aria hotel does disinfection. They don’t circulate 140 water all the time.

It’s inefficient and doesn’t eliminate the dead legs......they can’t circulate and hit all the piping.

I have countless customers who have an empty nest and the upstairs bathrooms are not used unless guests come once a blue moon. Huge dead ends.

What do you suggest ?
 
The rarely used bathrooms are addressed with piping. Instead of running a main trunk line with long branches, run your main as close to the fixture as practicable with a tiny branch. Or vavle them off. Technically you need a valve at every branch.

Also we're talking about fixtures that produce mist that can get into your lungs which would be the danger.


Just generally. Why do you think plumbing should be simple? Especially as technology develops and our knowledge increases. Why would old standards stay good forever? Why would you not want to sell things to customers that protect their health?

Health of a nation.
 
Homes aren’t built like that and cranking up water heaters will cause more injury than the hot water will do to stop legionella.

In your case, the cure.....very hot water will injure more people than the disease, legionella

If you can’t prove otherwise then Enjoy your opinion and I’ll enjoy my facts.


Burn injury from hot water is a major problem for healthy people. Legionella from their plumbing system is not.

Plumbing is simple until people try to complicate it.

Are circulating pumps required to run any amount of time ? No they’re not.

So how would cranking up the heat kill legionella in the piping ? It wouldn’t.

Even circulating the water wouldn’t hit all the piping. Sure you can get most, but not all.

How much legionella does it take to get sick ?

How large are bacteria ?

How much could fit in a 6” section of pipe ?

How much legionella can Live on a showerhead ?

Answer those questions......

Thanks buddy. 😬
 
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That video answers all of your questions. It's about an hour long.

Legionella is everywhere. We're not talking about eradicating it.
 
That video answers all of your questions. It's about an hour long.

Legionella is everywhere. We're not talking about eradicating it.

The video doesn’t answer my questions unless it agrees that you can’t kill legionella in a plumbing system by circulating water at 140.

And that’s what you started out saying.

Circulate a homes water system at 140. Go ahead and get sued.
 
I think the main difference in our thinking is your mainly talkimg about homes which I don't work on that often. I'm talking about bigger systems.

That being said mitigation is still, more and more, going to be the norm... That is unless they decide it won't be, lol.
 
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