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The Expansion tank does nothing for 2nd heater if the feed valve is turned but it is still running
The thermal expansion tank failed. That's a hundred gallons of expanding water on a 2-gallon expansion tank. After the first heater the hot water is delivered to the second heater on the cold side. These two water heaters will not be evenly worked and yes it will work this way but this is not the technical way to be installed
 

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..........but this is not the technical way to be installed
Like Redwood used to beat the drum about, needs to be piped in reverse return.

That CPVC is going to fail spectacularly one day.
 

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Was here to change the cartridge.


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Told the guy he needed to get the tile cut and he came out with this huge welding grinder and hacked the tile up. He scratched the hell out of the tub spout in the process. Also gave him the democrat tax cause I saw these

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Naturally..

130009
 

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Like Redwood used to beat the drum about, needs to be piped in reverse return.

That CPVC is going to fail spectacularly one day.
I don't know who Red Wood is since I'm kind of new here. No it needs to tee off of the cold line at even lengths and feed cold water to both units and then come up off the hot side and even links back to another tee. As well as a thermal expansion tank installed for both.

10 different plumbers will tell you 10 different things and they're not all necessarily wrong it's just a matter of experience. However one way will be the best.
 

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I don't know who Red Wood is since I'm kind of new here. No it needs to tee off of the cold line at even lengths and feed cold water to both units and then come up off the hot side and even links back to another tee. As well as a thermal expansion tank installed for both.

10 different plumbers will tell you 10 different things and they're not all necessarily wrong it's just a matter of experience. However one way will be the best.
You're suggesting to pipe them in parrallel(direct return), that won't always get you even length runs so they won't both be used equally.


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Easiest way to remember how to pipe reverse return is "First in, Last out".
 

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You're suggesting to pipe them in parrallel(direct return), that won't always get you even length runs so they won't both be used equally.


View attachment 130013

Easiest way to remember how to pipe reverse return is "First in, Last out".
I think you misunderstood his description or at least that image is not what he meant. I believe this immage is what he meant. Come down with the shared line and split it with a tee in the middle where both lines going to the heater is exactly the same length. By having the exact same length of piping from the point where it splits to 2 lines and same where is goes back from 2 to 1 gives you the most equal draw from both tanks.


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I think you misunderstood his description or at least that image is not what he meant. I believe this immage is what he meant. Come down with the shared line and split it with a tee in the middle where both lines going to the heater is exactly the same length. By having the exact same length of piping from the point where it splits to 2 lines and same where is goes back from 2 to 1 gives you the most equal draw from both tanks.


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That's why I used the word "always". Sometimes, as you drew it can have equal length runs, but you'll notice that in your example more elbows are used causing more restriction. It's not a big difference, but it's why the Reverse Return piping method is superior in all circumstances. It has the least amount of resistance to flow and asssures that the flow in both heaters will be the same.

If you go back and read some of Redwood's post you'll see there are other niche benefits too. His business focused on water heaters and he even had a website devoted to them in addition to several pages on his business's website.

10 different plumbers will tell you 10 different things and they're not all necessarily wrong it's just a matter of experience. However one way will be the best.

Parrallel isn't "necessarily wrong", it's one of the 10 different ways as you mentioned, but it's not quite as good. Reverse Return is THE best way to do it.


If you guys want to settle for 99% I'm cool with your choices ;)
 

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That's why I used the word "always". Sometimes, as you drew it can have equal length runs, but you'll notice that in your example more elbows are used causing more restriction. It's not a big difference, but it's why the Reverse Return piping method is superior in all circumstances. It has the least amount of resistance to flow and asssures that the flow in both heaters will be the same.

If you go back and read some of Redwood's post you'll see there are other niche benefits too. His business focused on water heaters and he even had a website devoted to them in addition to several pages on his business's website.




Parrallel isn't "necessarily wrong", it's one of the 10 different ways as you mentioned, but it's not quite as good. Reverse Return is THE best way to do it.


If you guys want to settle for 99% I'm cool with your choices ;)
I would not consider it settling but simply a matter of difference in what is the best option. A couple extra 90 fittings are not going to make any real difference in restriction to be noticed. By having a more equal draw and more equal usage you get a longer lifespqn before having to replace a heater. At the longer span you can then just replace both heaters and not have to worry about it again for many years to come. Your method 1 gets more use and now goes bad earlier but then it's not worth it to also replace the one with low usage. This the results in you having to deal with a replacement again sooner because the second one is already 1/2 way old and used. Sonas I see it your way ends up more expensive and more inconvenient over the years all just to have a couple 90 fittings less. In the end all those methods will get the job done.

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.......Your method 1 gets more use and now goes bad earlier but then it's not worth it to also replace the one with low usage. ..............
What are you talking about? The whole point of why I told him to use Reverse Return is because they will both get equal usage.
 

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I got the impression that it was still not an equal usage just closer to it. My bad then.

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No biggy. We do a lot of large water heaters in multiples for institutions, always piped inn reverse return. Hard to get a warranty claim through if they aren't piped correctly.
 

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So I went to a new home that had a sewer back up on his main floor... powder room toilet. He did have a full basement. Sewer went u through the foundation. Cameraed line and found this beauty... wanna take a guess what you are looking at? The winner gets a link to my ex wife's mfc cam girl videos

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Did someone glue the 3” 90 with a 2” LS90 stuck inside of it?
 

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No biggy. We do a lot of large water heaters in multiples for institutions, always piped inn reverse return. Hard to get a warranty claim through if they aren't piped correctly.
We pipe in a lot of multiple water heaters. Reverse return is always best practice. If you go into the computers on a set of heaters piped reverse return the hours and cycles are always very close. When you look at the same data on units piped “equal length” or “tree method” there is almost always one with significantly more hours and cycles.
 
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