Getting water to a manifold 25m away

[saveasteading]

Ater a good dicussion with a local plumber it is pretty certain that we will be putting 2 ashp systems in to supply 2 zones, but they will both be in one area next to one plant room.

The idea is that 1 big pump (15kW)would be working very hard, whereas 2 x 10 would be coasting and much more efficient.

Therefore the feed from the plantroom will need long distribution pipes to the manifold.

 

Ground floor concrete with ufh.

Partial First floor is largely in the roof space with timber floor and will be big rads. There will be a convenient void between low walls and the outer wall, through which services can run, and we can insulate inside the stone wall.

 

I think we must take the feed pipe to the first floor so that it can be insulated or we will lose too much heat in transit in the concrete floor.

 

Is it normal or wise to use the specialist insulated pipes, or simply to use normal pipe then pipe-wrap (the superior one) then also wrap in mineral wool.

 

This looks great but is £50/m, and it might be difficult to get round corners. Have used it previously outside from distant ashp to building but is it too much for inside?

.

[Conor]

I had this conversation at my plumbers supply which now does heatpumps. They reccomended the normal 28mm pipes with the outdoor wrapped insualtion. Main reason for this is that's it's half the cost and much easier to work with. 

[saveasteading]

4 hours ago, Conor said:

outdoor wrapped insulation.

Thanks, I didn't even know that existed. Presumably resistant to UV, water, bacteria etc.

35dia seems to be £10 for 2m , so for 2 pipes is £10/m x 35m = £350 instead of 35 x £50 = 1,750...I like it.

 

 

Ours will be in the dark, so only heat effects and rodents as threats.  I think we would lay mineral wool on top as a secondary insulation and that is sorted.

[JohnMo]

Not sure of you ground floor make up.  But could you bury these pipes in your floor insulation, use that as your insulation, put them in flex conduit so they are replacable to comply with building regs.

[saveasteading]

2 minutes ago, JohnMo said:

could you bury these pipes in your floor insulation,

Clever thought, and tidy.

But  I am reluctant to feed this full temperature pipe within the PIR  at  the reduced cover that would ensue.

 I thought of simply putting them in the ground-floor screed but am feeling that the floor is full enough of feed pipes and distribution pipes.

[TonyT]

6 hours ago, saveasteading said:

Thanks, I didn't even know that existed. Presumably resistant to UV, water, bacteria etc.

35dia seems to be £10 for 2m , so for 2 pipes is £10/m x 35m = £350 instead of 35 x £50 = 1,750...I like it.

 

 

Ours will be in the dark, so only heat effects and rodents as threats.  I think we would lay mineral wool on top as a secondary insulation and that is sorted.

Google armaflex  it’s For outside just like it’s other closely named product climaflex is for inside.

 

[saveasteading]

32 minutes ago, TonyT said:

armaflex

Yes I found it. I have used normal stuff outside, not knowing of this, and it fails in sunlight.

 

As this would be in a dark void indoors, is Climaflex or Armaflex class O equally good.

 

I see it is 'unsplit', which makes insulation sense, but does that make it difficult to put on the pipe?

 

[TonyT]

You get it in sheets and in standard pipe sleeves.

 

https://www.insulationsuperstore.co.uk/user/u/pimp/uploads/attachments/4/armaflex-installation-guide.pdf

 

 

 

[saveasteading]

That is a lot of information.

Basically it comes un-slit for sliding onto new pipes and slit (but with pre-glued edges) for retrofit.

and there is glue for joints and ends.

 

I like it.

[PeterW]

Armaflex (or any Nitrile Rubber insulation) is not UV stable. You need to use the correct ones for outside or cover them with a coating. 
 

Been discussed recently 

 

 

[saveasteading]

On 20/01/2022 at 00:07, PeterW said:

Armaflex (or any Nitrile Rubber insulation) is not UV stable

Thanks. in this situation it will be indoors in the constant dark.

 

[Nickfromwales]

If this is internal, then I'd also say run 28mm pipe ( copper or Hep2o ) and insulate yourself. As the delta between the pipe and the ambient temp of its surroundings are minimal, there is no real reason to go for pre-insulated afaic. Also, the pre-insulated pipes have a bending radius of around 1m, varies with external diameter based on how thick an insulation you went for, so near impossible to navigate tight bends also. I am using Primo Uno on an upcoming ASHP install where the runs are circa 30-32m from the heat pump, so I'm maxing out the insulation levels by running 2x Uno with thickest insulation available vs 1x Duo with limited, albeit still very good, insulation.

For you, deffo stick with regular pipe and if you use Hep2o you can go very long distances with no joints, and then just slide un-slit sleeves of pipe insulation down each one. Then clip the pipe and insulation into place with either plastic waste pipe clips or powder coated all-round band ( from electrical merchant ).  

[saveasteading]

Thanks Nickfromwales.  I was up in the attic of our house (not the project) and noticed how the pipe lagging was barely encircling the pipes, and had gaps between lenghths, so it has shrunk both directions over many years. It was probably the cheapest make going, and I am thinking it best to buy branded in future. Gluing must help, and straping as you suggest.

Thanks for the info that the lagging slides on un-slit: I had imagined it being tight.

[TonyT]

One great idea I saw on another forum was that once insulated, this chap used different colour coded cable ties for each different function, such as hot cold, flow and return etc. Easy for tracing /isolation 

[saveasteading]

2 hours ago, TonyT said:

different colour coded cable ties for each different function, such as hot cold

Simple but clever. Electrician's tape would fall off in time, cable ties won't, and will hold the insulation on.