PEX manifolds, where have I gone wrong?

[jemibu]

Have you ever reached the end of a marathon and decided "hmm I'm not sure I like the way I ran, I want to try it again"? I am replacing the plumbing in my 1940's 1 1/2 story single family house in Minneapolis. Open system, fairly clean city water. Galvanized pipe run amok through the house. Months ago I designed and installed a PEX remote manifold system parallel to the original. The intent is to replace the final few feet of fixture lines over a weekend.

In retrospect I wonder if I've make poor decisions though. Not mistakes. Just dumb choices. So I've come here to get railroaded by those with more experience. Or, have the confidence instilled to wrap up the install on the current layout

Here's the first replacement
Mind you, I've already run these lines and have paid for and connected a lot of LF brass. But I'm not opposed to ripping out and starting over. Now's a good time to mention that I'm a sadist.


Layout version 1




Primary manifold




Example of one of five remote manifolds tucked between floor joists




New system not connected to city water supply yet

But in hindsight...

1. The distances between sources and fixtures are short. But my runs and volumes are abnormally high. It's going to take a long time to get hot water. As mentioned before, I'm a sadist and am impatient to get scalding hot water.
   
   
2. Maybe a dedicated recirc line from each manifold will help . But some remote manifolds be 'preferred' when the pump pushes hot water toward the primary manifold.
   
   
3. I overlooked that silcocks don't need filtration
   
   
4. Install looks fancy but why the hell do I need to shut off one zone at a time? That's a lot of brass fittings and potentials for leaks (*NOTE access panels will be put in the drywall to get at every manifold. No other connections are behind walls. I planned for leaky fittings even though I tightened the bejesus out of them)
   
   
5. I discovered how much I really love gauges and valves

Which that brings me wanting to tear everything out and install an Uponor Logic layout with a dedicated recirc line:


You'll notice I added a bathroom. Magic! Capped until the bathroom is actually added.

So... would starting from scratch give me such a better system that it's worth the effort to replace the replacement?

 

[FullySprinklered]

Looks like you had fun with it. I'd hook it up and see how it performs, then if something's wrong fix it. I would reroute the lines to the spigots. Save the filter.

 

[Sponsor]

 

[hj]

You are NOT a "sadist". You are a masochist.

 

[jemibu]

You are NOT a "sadist". You are a masochist.

You sir are correct, I mixed that up!

Looks like you had fun with it. I'd hook it up and see how it performs, then if something's wrong fix it. I would reroute the lines to the spigots. Save the filter.

I made the city inspector chuckle. I think “overbuilt” was the word. Yeah I had fun with it!

 

[Reach4]

You could change the hot branch lines to 3/8 and 1/2 inch as appropriate.

 

[jemibu]

You could change the hot branch lines to 3/8 and 1/2 inch as appropriate.

So replace 3/4 hot lines to each remote manifold with 1/2, and 1/2 hot lines to each fixture with 3/8? Hadn’t thought of that

If I keep this layout and run into issues that would be the first change

The galvanized lines aren’t at critical blockage yet so I have some time to noodle on this. And the honeydo list points me elsewhere at the moment

I come back to... what would someone smarter than me do if this was their house and had the time and budget to play

 

[Bcarlson78248]

One small change in configuration that I made was to orient the manifolds horizontally, so that all the outgoing water pipes went straight up. I also put the the hot/cold manifolds under/over, so that all the feeds lined up. For example, the far left output on both manifolds would be a for a bathroom sink, and the output lines could be run together. This simplified the routing and reduced the need for long sweeps or right angle fittings.

I also used copper manifolds that included a shutoff for each line. I just had to crimp the PEX onto each line. The attached picture is from the back side, so you can't see the shutoff handles. The shutoffs face the other direction, and are accessible by opening up a metal panel cover. These manifolds are a through feed, so, so there is a 3/4" lines in and out, and 1/2" supply lines. There are also more blue than red lines, since it included a line for a hose bib.

Bruce

 

[parksfolk]

I am re-plumbing my entire house and am leaning towards the proposed configuration in the 1st message above. So after a year has passed, can we get an update on your findings? Did you go with the original plan, and do you have any regrets? Thanks!

 

[gentoo]

We are going to be moving the water heater, furnace and laundry from the garage to a new utility space and new laundry room. I did some searching around and I was inspired by this thread to design a hot/cold fresh water system for my house. This system will feature supply manifolds for primary distribution and service manifolds for local distribution.

The supply manifolds are all specified to be 1-1/4" header with 1" inlet, 1" passthrough and 3/4" outlets. The only exception to this general construct will be the cold water supply manifold in the utility room. It will also have a 1" outlet for the hot water heater. The service manifolds are all specified to be 1" header with 3/4" inlet and 1/2" outlets. The only exception to this general construct will be the hot water service manifolds that will have recirculation will be outfitted with a 3/4" outlet. The recirculation manifold are specified to be 3/4" inlets and a 1" outlet.

Like previous posters, I'd like feedback on the pros and cons, plusses and minuses, genius and lunacy of this proposal. All input, except for ad hominem attacks are valid and valuable.