Cold water return loop?

[stas]

Hi,

I was thinking about setting up the plumbing of my cold water in a loop (like a hot water return). So i would have the one line branching off to everything then another line going from the begin of the main water line to the furthers cold water tap.

Does anybody advise me if this would have any benefits e.g. if a separate tap is turned on while somebody is in the shower the shower tap may not get a pressure drop as much? Or would this be a pointless addition?

Any help would be appreciated thanks guys

 

[frodo]

before i says pointless,

what are your issues?

what is the piping material now ?

 

[stas]

I want to get the same principle as a circular manifold so you dont feel pressure drops when somebody flushes the toilet and your in the shower e.t.c ([ame]https://www.youtube.com/watch?v=cy9w7bNJWfY[/ame]).

It is a new build all pex, plumbing is in but no walls as of yet so i will be able to modify it relatively easily

 

[frodo]

ok,,,,new build. what size is the pipe from the meter to the manifold?
what size pipe is from the manifold to the fixtures ?

is it plumbed with 1 manifold ?
everything out to fixtures from there?

 

[frodo]

that guy is funny, i could only watch 3 minutes ..fell out of my chair laughing and got my foot tangled in the mouse wire.

and spilt my coffee....seriously ? a test port? with out it he would have to cut into the line ?

LOL...

screw it on the outside hose bib....

 

[stas]

lol.

the mains entering is 25mm and reduces to 20mm pex pipe when it comes in the wall. The fixtures are hot water service is 20mm but for toilets and shower e.t.c they branch of to 16mm.

and the moment it is plumbed straight through (no manifold) branching off to a dead end, but was thinking if i attached the second 20mm pex line from the begging and reduced to 16mm at the furthest exterior tape or possibly hot water service it would generate the water from both sides to create the manifold like effect?

I have attached a picture i found on the web of a hot water return loop i guess itr would be similar to but minus the pump.

 

[KULTULZ]

I finally got an answer on why the manifolds and home runs on a PEX system... No (or little) drop on service pressure @ fixtures...

that guy is funny, i could only watch 3 minutes ..fell out of my chair laughing and got my foot tangled in the mouse wire.

and spilt my coffee....seriously ? a test port? with out it he would have to cut into the line ?

LOL...

screw it on the outside hose bib....

I found it very informative myself. Of course I am a rookie and you are a pro.

The test port @ the manifold makes perfect sense to me as one would not have to go outside of the house to monitor supply pressure.

 

[frodo]

I finally got an answer on why the manifolds and home runs on a PEX system... No (or little) drop on service pressure @ fixtures...





I found it very informative myself. Of course I am a rookie and you are a pro.

The test port @ the manifold makes perfect sense to me as one would not have to go outside of the house to monitor supply pressure.

he said, the only way to check the psi was either his test port or to cut into the main line.

i am pointing out, that statement is false, all you need to do is screw a gauge on a hose bib,

i dont have a problem walking outside,

 

[KULTULZ]

he said, the only way to check the psi was either his test port or to cut into the main line.

i am pointing out, that statement is false, all you need to do is screw a gauge on a hose bib,

i dont have a problem walking outside,

Yeah, but you are on the clock and HE is flat rate...

 

[frodo]

....................

 

[stas]

ok so by the image the cold line without pump would be of benefit?
would it also benefit from putting a hot line without a pump or would that just waste more water before getting it hot?

 

[stas]

ok so by the image the cold line without pump would be of benefit?
would it also benefit from putting a hot line without a pump or would that just waste more water before getting it hot?
stas is online now Report Post

 

[Caduceus]

A pressure balancing loop is not necessary for a whole house and is typically used at the fixture when multiple fixture heads (like in a dual shower or shower/body sprayer) are installed. The problem that most people experience when flushing a toilet and getting blasted with hot water from the shower is more related to volume, but pressure is still a consideration.
The hot and cold water distribution piping must be properly sized to accommodate all fixtures as if they were all being used simultaneously. The water pressure must also be adequate for normal operation and will be affected minimally as long as the volume meets the sizing requirements.
Shower valves with balancing spools (thermostatically balanced) are also a must especially if your piping is already under sized. A drop in water pressure on an under sized distribution system will occur throughout the piping in the house and would also be reflected in a loop for the whole house. A loop at the fixture is installed after the control valve and still needs the proper sizing to be effective which is why some home owners still experience pressure drops with a loop installed on newly remodeled dual/body spray showers.
In my opinion, the whole house loop will have no effect on a plumbing system where the volume and pressure have already been established and is showing weakness of performance.

 

[Caduceus]

If you install the loop and it shows an improvement in pressure balance throughout your home, please post the results. I certainly don't mind if I'm corrected and given an opportunity to learn something new.

 

[KULTULZ]

If you install the loop and it shows an improvement in pressure balance throughout your home, please post the results. I certainly don't mind if I'm corrected and given an opportunity to learn something new.

I know I learned something.

THANX!

 

[frodo]

ok so by the image the cold line without pump would be of benefit?
would it also benefit from putting a hot line without a pump or would that just waste more water before getting it hot?
stas is online now Report Post

in my opinion a cold loop is a waste of time and materials <<<IF>>>the piping is of adequate size.

I can see the benefit if the piping is undersized.

you could benefit from a hot loop with pump.

i would suggest instead of pump running 24/7 or an aqua stat

the farthest bathroom light switch control the pump
with a 3 way switch at the guest bath

 

[KULTULZ]

...bear with me here...

Instead of having the manifolds at the service entry (and all of the home run tubing), would it be better to run trunk and branch (min. 1" PEX) with the cold water (and hot water loops) @ the fixture sets (bath-kitchen-laundry-etc.) and make it somewhat simpler to comply with ASSE 1070?

 

[stas]

I have the material already so i may add it to the cold anyway as i wouldn't think it should have any negative effects? unfortunatly i wouldn't be able to say if it has had any effect though as there is no showers/toilets installed to test the difference...

The only think i could think of if i attached to hot aswell without a pump it would take longer to flush out all the extra cold water in the lines sitting there. So may not be worth it in that regards

 

[frodo]

I have the material already so i may add it to the cold anyway as i wouldn't think it should have any negative effects? unfortunatly i wouldn't be able to say if it has had any effect though as there is no showers/toilets installed to test the difference...

The only think i could think of if i attached to hot aswell without a pump it would take longer to flush out all the extra cold water in the lines sitting there. So may not be worth it in that regards

install the hot water loop

valve it off till you can afford a pump

 

[stas]

Do you mean a shut off valve? wouldn't that still defeat the purpose of filling a line with wate that will have to be flushed out cold??

install the hot water loop

valve it off till you can afford a pump

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