starting plumbing

[Simplysimon]

hi all,

starting the plumbing and was going with @Nickfromwales idea of two manifolds, i need a hot return due to length of run from cylinder to furthest outlet. can i have manifolds as well as a pumped return? read through topic below, i did post as a link but it came up as below. had thought of going 10mm but will probably go with 15mm plastic though thoughts welcome please

[JohnMo]

No issue that's what I did.  Take the return pipe to the furthest outlet, pump (suitable for potable water), check valve, and back to cylinder.

[Iceverge]

How far from your cylinder are the outlets? I ran a 10mm pipe 13m to the kitchen tap and have hit water in 9 seconds at worst. Flow rate isn't hectic at 5-6l/m but quite acceptable. I did keep the hot manifold directly off the hot cylinder outlet mind you. 

 

Interesting at least a third of the delay was due to the internal volume of the tap. 

[Conor]

Check your static water pressure at your house. I've gone for 10mm pipes for all washbasins and WCs. When we connected up last week, the main bathroom washbasin was little more than a trickle, just about enough. (~13m pipe, up two stories) We've 3bar static with 25mm pipe all the way to the manifold.

[Simplysimon]

19 hours ago, Iceverge said:

How far from your cylinder are the outlets?

21m to the furthest

 

On 15/01/2022 at 19:02, JohnMo said:

No issue that's what I did.  Take the return pipe to the furthest outlet, pump (suitable for potable water), check valve, and back to cylinder.

do you mean that the pipe to the furthest point taken from maifold is then returned to cylinder? that being the case the other points won't have the return from them, therfore cooling down. i was under the impression the pumped return would reduce heat loss as the drawn water to the tap doesn't cool down therefore requires less heating up and had almost instant hot to tap.

[JohnMo]

Somewhat lost me.

First point, yes

Second point, you didn't ask for that, you asked for the furthest point for secondary return with manifold. If you want it at all outlets, that could be done.  The flow will go through the manifold so that is also heated. So all outlets close to manifold get hot water quickly.

 

No a secondary return does not save any energy, as you are pumping hot water around a circuit and it will loose heat constantly, hence a need to insulate well.  It save running cold water down the waste while you wait for the hot water to arrive.

 

I have mine on a timer so it only runs when I am most likely to want it, to save energy.