New construction water supply and recirc loop

[Timberwolf78]

Hello
Looking for some advice on how to plan the hot water recirc for my situation.

Background/Current state:
New construction that had been put on hold for a little bit. The plumber ran most of the water lines that are shown in the attached diagram. Now I am going to start where it was left off.
There is a tank water heater in the mech room.
there are 2 3/4" pex B "trunks" that go from the mech room to the other side of the house which is appx 55 feet away and where most of the bathrooms/fixtures are. all fixtures are stubbed in connected via multi-port tees.
The kitchen is right above the mech room. and the laundry and a powder room is just left of it. thqt's basically a 3rd 3" trunk.
Plan:
I would like to add a dedicated recirc loop and use taco 006e3 ecm circulator setup. How do I best accomplish that?
Since there are multiple "trunks", how do I best run the loop that is connected to all 3?

Thanks in advance.

 

[John Gayewski]

Your diagram is lacking good info. But the hot water should be a giant loop. If it's not possible for the hot water to be a loop then you need balancing valves to control the flow in each trunk. This is a less desirable way to do it.

Your 006 might be too big for what your trying to do. What type of circulation are you attempting?

 

[Sponsor]

 

[Jeff H Young]

those ballancing valves for multiple loops are often called " circuit setters" 3 return lines tie together someplace with the ballance valve acessable you could have them join at water heater or else where

 

[Timberwolf78]

Thanks!
There are 6 3/4' main lines(3 hot and 3 cold) that start in the mech room.
4(2 hot and 2 cold) run all the way to the other side of the house in parallel. both stacks terminate at different bathroom fixtures and are not connected to each other at the moment. they are connected to the fixtures with individual 1/2" pex lines.
Basically all 3 trunks are roughed in but hanging above the water heater and not connected.
What other info would help?

"If it's not possible for the hot water to be a loop then you need balancing valves to control the flow in each trunk. This is a less desirable way to do it."
That's kind of what I am trying to get opinions on. How can I create a single loop with the 3 trunks that are already there and based on the location of the water heater?

 

[Timberwolf78]

those ballancing valves for multiple loops are often called " circuit setters" 3 return lines tie together someplace with the ballance valve acessable you could have them join at water heater or else where

Thanks
That's what I am trying to avoid if possible.
But If I were to go this route then it means running 3 new return lines, each teed into the hot supply of the furthurest fixture from the heater and joined at water heater with 3 balancing valves?
Did I get that right?

 

[Jeff H Young]

yea that works i like the location as well. then you need to think about when pump runs alll the time? or 1 2 or 3 thermastats ? plus a timer . I was wondering if a thermal valve on all 3 besides a circuit setter would make sence. if no circulation is needed on one branch no need to that branch to circulate but on other hand the other 2 might need it . Im kinda overthinking it a bit but just some things to concider. a well working hot water circ system is real nice to have and I dont think the cost is that bad in some ways your saving but luxurious to have hot just leke that good luck on it!

 

[John Gayewski]

It depends on how instant you want the water to be hot at each fixture. If you kitchen is right by the heater you probably don't need to bit to circulate hot water. Same with the laundry. No reason to have instant hot water for laundry.

Mostly the bathrooms. If those two trunks are close enough to the bathrooms where circulating got hot just from one end of the basement to the other and back to the heater will give you instant hot water then you could just connect them there.

Otherwise you will want to run a recirc line from each bathroom back down to the heater and have them connect at the inlet of the pump with balance valves there. Can't say much without a good iso.

 

[Timberwolf78]

Hey again
So I created this new iso just depicting hot water supply, that may help explain things better.
I marked 3 main trunks as 1, 2, 3.
Trunks 2 and 3 run in parallel right next to each other that go appx. 50-55 feet from the mech room all the way to the other end of the house. Each trunk serves 2 bathrooms (total of 4 baths)
The kitchen, that is served by trunk #1 is right above the mech room.

 

[Jeff H Young]

great You might need to go overthat with your plumber to make sure you are both on same track .

 

[Timberwolf78]

Thanks!
I am the plumber now
I have most of the pex lines roughed in.
What I am trying to figure out is how to run the recirc lines based on my setup. something that is the least complicated with the least amount of moving parts(mixing valves) ideally.
Since it's new construction and walls and floor trusses are open, I am ok with any amount and size of pex that I would need to install.
1. run recirc lines back to the water heater for each of the 3 trunks - so 3 separate lines -
(it would be 3 half inch lines connected to mixing valves at the heater?)
2. run 2 lines each for trunk #2 and #3 but leave #1 since both the kitchen and laundry are like 10 feet from water heater.
(2 half inch lines connected to mixing valves at the heater?)
3. connect #2 and #3 where the bahrooms are and run 1 line back to the heater.
(If I go with this option, should I use a 3/4" or a 1/2" pipe?)

or something else?

 

[John Gayewski]

Thanks!
I am the plumber now
I have most of the pex lines roughed in.
What I am trying to figure out is how to run the recirc lines based on my setup. something that is the least complicated with the least amount of moving parts(mixing valves) ideally.
Since it's new construction and walls and floor trusses are open, I am ok with any amount and size of pex that I would need to install.
1. run recirc lines back to the water heater for each of the 3 trunks - so 3 separate lines -
(it would be 3 half inch lines connected to mixing valves at the heater?)
2. run 2 lines each for trunk #2 and #3 but leave #1 since both the kitchen and laundry are like 10 feet from water heater.
(2 half inch lines connected to mixing valves at the heater?)
3. connect #2 and #3 where the bahrooms are and run 1 line back to the heater.
(If I go with this option, should I use a 3/4" or a 1/2" pipe?)

or something else?

Third option. Use 3/4" pipe to connect them.

 

[Jeff H Young]

I think a single loop is better , 4 bathrooms Ive had it size out to a 1 inch main on the hot and that was copper so with pex you are probebly close and Im guessing 90 percent run all 3/4 but its probebly close to requiring 1 inch