PEX Homerun System Setup??

[mcintoshmc]

Someone suggested the home run system, and after doing some research, I really like that setup. So, this what I got so far.

Guest Bathroom
Shower - 1 Hot/1 Cold
Sink - 1 Hot/1 Cold
Toilet - 1 Cold

Washer/Dryer
1 Hot/1 Cold

Kitchen
Sink - 1 Hot/1 Cold
Dishwasher - 1 Hot

Master Bathroom
Shower - 1 Hot/1 Cold
Sink - 1 Hot/1 Cold
Toilet - 1 Cold

Water Heater
1 Hot/1 Cold

Front/Back Yard Spigot
2 cold

TELL ME IF MY THINKING IS CORRECT

I found a 24 port manifold.

1- Blue 3/4 PEX line from water meter to manifold cold water main
2- 1/2 Blue line from manifold to water heater
3- Red line from manifold hot water main to water heater
4- Then 1/2 red and blue lines from manifold to each fixture

QUESTIONS??

1) Based on what I described, 3/4 will be coming in from the meter, but 1/2 to the water heater, yet it will be 3/4 from the water heater to the manifold. Doesn't make sense to me. Can you explain?

2) There will be ball valves for each port, where do people normally place the manifold, so it is accessible?

3) Did I miss anything?

 

[stevemachine]

I would suggest 3/4 to the water heater. Tee off of the pex from the meter. Electric or gas heater? If its gas you can't run pex to the water heater because anything combustible needs to be six inches away from the vent, unless its b vent its 1". Also dishwasher I would tee off the hot under the kitchen sink, you don't have to run a seperate hot for the dishwasher. Other than that I think you pretty well got the idea down pat.

 

[stevemachine]

And if I remember correctly you are in a crawl space right? Usually people put a header in the joist space, at least that's where I've always put mine.

 

[stevemachine]

Also not sure if you ever plan to add fixtures in the future but some people go with headers with extra ports then cap them off, that way if you want to add something you can still go off the home run system.

 

[mcintoshmc]

I would suggest 3/4 to the water heater. Tee off of the pex from the meter. Electric or gas heater? If its gas you can't run pex to the water heater because anything combustible needs to be six inches away from the vent, unless its b vent its 1".

Gas. So, I currently have galvanized to the heater. I think I'll have to run pex to copper, to keep it 6 inches a way.

 

[mcintoshmc]

And if I remember correctly you are in a crawl space right? Usually people put a header in the joist space, at least that's where I've always put mine.

When you say header, you're talking about the manifold right? And if you put it in a joist space, then that means you have to go under the house to shut off water right? How close should the header be to the water heater?

 

[stevemachine]

Gas. So, I currently have galvanized to the heater. I think I'll have to run pex to copper, to keep it 6 inches a way.

Ok good call! I've seen people run plastic pipe less than six inches to the vent but its not worth the risk.

 

[stevemachine]

When you say header, you're talking about the manifold right? And if you put it in a joist space, then that means you have to go under the house to shut off water right? How close should the header be to the water heater?

Yes, header is a manifold. That would be correct. You can really put it wherever you want. I figure as much as it sucks, if you do it in the crawl space then once you drill your holes from the floor it's not bad to run. If ya put the header upstairs then it may involve drywall. And usually headers are within a few feet of the tank. There's no particular rule for that, that I know of. How far are your runs? Like what's your longest? Just a ball park, out of curiosity.

 

[mcintoshmc]

Still haven't decided completely where to put the manifold, that's the toughest part for me, but the longest run from the heater is about 35 feet

 

[stevemachine]

Ok well I mean for the placement of the header you just gotta try and think of the whole picture, the main thing is, put it in a spot where you can do all of your take offs easily, like do it in a wide open joist space. Ah I usually figure the fine details out once if got the header in my hand. But maybe that's just me

 

[mcintoshmc]

I'm thinking I could attach it to a joist near the crawl space entrance, but I would be 30 feet away from the water heater. Or I could open up the drywall and create an access panel between a stud.

 

[mcintoshmc]

This is what I'm working with

 

[Crackplumbers]

The first thing that you must have is two headers one for the hot lines and one for the cold lines. The main water feed for cold and hot must be 3/4 inch for this type of system to work correctly.

 

[stevemachine]

Yeah depends on what you want, there's a million ways you can do it. I just do it the easiest way lol but if you find cutting drywall easier or put it further away from the tank easier then do what ever you want. With water lines there's not a lot of rules to follow. Just again like we stated in previous posts. 3/4 feeding the header and 3/4 feeding the tank. Other than that just do what makes the most sense to you. It's kinda like a double edged sword, whether you put it 30 ft away or you make an access. I guess if I was doing it and it was reasonable I would put the headers the closest to the "source" so the water heater and the main water if its not a total pain. Usually that's what it is in most houses.