My self-build DIY plumbing

[Thorfun]

13 minutes ago, Nickfromwales said:

Of course. Us professionals cannot possibly allow you, as a newbie, to get this right first time now can we?! 
So;

 

 

OK.

The rest bend will eventually fall off. Do as Bruce says above, and clamp that well. The shoe on the bend is supposed to be where the thud gets arrested, but that’ll be off before you know it  

Right. So the force of the solids sliding down from above will force the bend off! Got it and not something I really want to happen. 
 

I’ll strap it up some more tomorrow and report back. 
 

thank you. 

[Dan F]

4 hours ago, Thorfun said:

I have read many discussions on here about the size of pipe and have decided for simplicity to simply run 15mm everywhere and the HRC in 10mm. I know I could do the basins in 10mm but if I'm running an HRC to them then that will clear the dead leg and so I can use the 15mm without worrying about that side of it.

 

15mm copper of plastic?  15mm hep2o is only 11mm ID and, depending on how far away your showers are and what flow rate you want.. might be tight.   It's one thing If your showers are close and/or you are good with 8L/min, but if they are 20m away and you are expecting 15L/min, you need to size accordingly.

 

[Russell griffiths]

18 hours ago, Russell griffiths said:

Don’t forget to strap the life out of that rest bend. 

It’s not near the rest bend. 

that Bend will blow off the end of the pipe with the downward splat and whoosh of last nights kebab. 

[Thorfun]

13 minutes ago, Russell griffiths said:

It’s not near the rest bend. 

that Bend will blow off the end of the pipe with the downward splat and whoosh of last nights kebab. 

👍. will get it sorted!

[Thorfun]

10 hours ago, Dan F said:

 

15mm copper of plastic?  15mm hep2o is only 11mm ID and, depending on how far away your showers are and what flow rate you want.. might be tight.   It's one thing If your showers are close and/or you are good with 8L/min, but if they are 20m away and you are expecting 15L/min, you need to size accordingly.

 

plastic. furthest shower that I care about is 10m away from the manifold.

[Russell griffiths]

3 minutes ago, Thorfun said:

👍. will get it sorted!

Move that other bracket closer to the join as well, you will get movement at the join due to the rubber. 

Try to strap close to joins and then work away from that. 

[Thorfun]

4 minutes ago, Russell griffiths said:

Move that other bracket closer to the join as well, you will get movement at the join due to the rubber. 

Try to strap close to joins and then work away from that. 

I'll just add another one at the join nearest the rest bend and use strap band around the 'foot' at the base of the rest bend. 

[Pocster]

50 minutes ago, Thorfun said:

plastic. furthest shower that I care about is 10m away from the manifold.

My shower is around 16m away from manifold . 15mm pipe no issue 

[Thorfun]

1 hour ago, pocster said:

My shower is around 16m away from manifold . 15mm pipe no issue 

one of the jobs to do on my list is to check my static pressure and flow rate just so I can double check everything.

[Pocster]

1 minute ago, Thorfun said:

one of the jobs to do on my list is to check my static pressure and flow rate just so I can double check everything.

Must admit I didn’t bother with any of that . I had a new water main put in ( assume you did also ) . Instantly I could see how much better the water pressure was ( we used to live next door to the plot and water pressure was ok ish - old pipework ) 

[Thorfun]

10 minutes ago, pocster said:

Must admit I didn’t bother with any of that . I had a new water main put in ( assume you did also ) . Instantly I could see how much better the water pressure was ( we used to live next door to the plot and water pressure was ok ish - old pipework ) 

yeah. new 32mm main direct from the pipe in the road. our existing supply off the water main in the road is shared with 2 other properties so I'm expecting a better pressure/flow. I'm just curious is all! just one of those things that my brain needs to know.

[Russell griffiths]

Some of my thoughts, I could be completely looking at it the wrong way. 

You are measuring how far away your cold is from the shower. 

So what. 

If you are running a hot return to the shower, that is blended down to 45 degrees for arguments sake at the point of origin, then you won’t be feeding much cold in to the mixer valve at the shower end, as it’s already at a good temp. 

So 90% of the water coming out of the shower is from the hot return.  

Right or wrong. 

[Thorfun]

1 hour ago, Russell griffiths said:

Some of my thoughts, I could be completely looking at it the wrong way. 

You are measuring how far away your cold is from the shower. 

So what. 

If you are running a hot return to the shower, that is blended down to 45 degrees for arguments sake at the point of origin, then you won’t be feeding much cold in to the mixer valve at the shower end, as it’s already at a good temp. 

So 90% of the water coming out of the shower is from the hot return.  

Right or wrong. 

I'm not planning a hot return for the shower but the hot and cold will be the same distance (give or take a short amount for the difference between the hot and cold manifolds). I can only presume that in a pressurised unvented setup the water pressure for the hot and cold are the same? so I'm also presuming that with a blended temperature at the shower end it's not an accumulation of hot + cold water pressures, right? therefore measuring the cold feed water pressure/flow rate will give an indication as to the flow rate at the shower head?

[Pocster]

1 hour ago, Thorfun said:

I'm not planning a hot return for the shower but the hot and cold will be the same distance (give or take a short amount for the difference between the hot and cold manifolds). I can only presume that in a pressurised unvented setup the water pressure for the hot and cold are the same? so I'm also presuming that with a blended temperature at the shower end it's not an accumulation of hot + cold water pressures, right? therefore measuring the cold feed water pressure/flow rate will give an indication as to the flow rate at the shower head?

Run the 15mm pipe . Stick the shower on the end pointing into a bucket . You’ll see the result for real . All this blended BS is 💩; so I have to wait 8 seconds for my shower to get hot from the uvc - who cares . 

[Thorfun]

1 minute ago, pocster said:

Run the 15mm pipe . Stick the shower on the end pointing into a bucket . You’ll see the result for real . All this blended BS is 💩; so I have to wait 8 seconds for my shower to get hot from the uvc - who cares . 

I'm not worried about the shower and the dead-leg removal tbh. my shower controls will be outside of the shower tray so I can start the shower without getting wet and can wait the few seconds for it to get to temperature. 

 

the HRCs will be on the basins as I hate waiting for hot water when wanting to wash my hands!

[Pocster]

5 minutes ago, Thorfun said:

the HRCs will be on the basins as I hate waiting for hot water when wanting to wash my hands!

Fussy (expletive deleted) 

[saveasteading]

23 hours ago, Nickfromwales said:

as Bruce says above, and clamp that well. 

Agreed. One flush could spring the bend off the vertical pipe. If not the first then soon after guaranteed.

[Nickfromwales]

9 minutes ago, saveasteading said:

Agreed. One flush could spring the bend off the vertical pipe. If not the first then soon after guaranteed.

Especially if they’re vegans lol. 

[SteamyTea]

10 minutes ago, Nickfromwales said:

Especially if they’re vegans lol. 

Cured my haemorrhoids going out with a vegan.

Just had a donkey kebab for my tea, roll in the morning coffee, the French know it loosens anything. 

[Dan F]

8 hours ago, Thorfun said:

plastic. furthest shower that I care about is 10m away from the manifold.

OK.  Some of ours were 16m away and flow rate isn't great (even with new 32mm main).  We also used 16mm MLCP.    It may be partly down to the showers we used, but the fact dyanmic pressure after PRV and water softener is <2.5bar doesn't help either.

[Nickfromwales]

24 minutes ago, SteamyTea said:

Cured my haemorrhoids going out with a vegan.

🤢🤮

 

25 minutes ago, SteamyTea said:

the French know it loosens anything. 

and if not, wash it down with some frogs and snails……. Wtf 😳. 

[Thorfun]

42 minutes ago, Dan F said:

OK.  Some of ours were 16m away and flow rate isn't great (even with new 32mm main).  We also used 16mm MLCP.    It may be partly down to the showers we used, but the fact dyanmic pressure after PRV and water softener is <2.5bar doesn't help either.

Can you change the PRedV to allow a higher pressure?

[Dan F]

33 minutes ago, Thorfun said:

Can you change the PRedV to allow a higher pressure?

Yes, now set to 3.5bar and this helps. But doesn't negate the almost 1bar of loss those runs have (0.4 due to elevation and 0.6 due to pipe), so shower still only gets around 2bar.  This translates to a satisfactory flow rate of 10-12L/min, but not quite as much as I'd expexted.

 

[Thorfun]

3 minutes ago, Dan F said:

Yes, now set to 3.5bar and this helps. But doesn't negate the almost 1bar of loss those runs have (0.4 due to elevation and 0.6 due to pipe), so shower still only gets around 2bar.  This translates to a satisfactory flow rate of 10-12L/min, but not quite as much as I'd expexted.

 

 

so I'm presuming that if I do as @pocster suggests:

 

3 hours ago, pocster said:

Run the 15mm pipe . Stick the shower on the end pointing into a bucket . You’ll see the result for real .

 

for each outlet once the pipe is run and connected up I can get a real world idea of actual flow rate and as long as that's before I board everything I can always run a larger bore pipe? the beauty of a manifold system I guess.

[Dan F]

1 hour ago, Thorfun said:

 

so I'm presuming that if I do as @pocster suggests:

for each outlet once the pipe is run and connected up I can get a real world idea of actual flow rate and as long as that's before I board everything I can always run a larger bore pipe? the beauty of a manifold system I guess.

No, I don't think you can do that.  1.5bar. 2bar or 2.5bar dyanmic pressure (or whatever you have after losses) will give different flow rates through a shower mixer+head than just out the end of a 15mm pipe!

 

Aside from the theory I know this from practical experience as, when I was trying to work out why I only got 7-8L/min from shower, I took the whole mixer body out and then measured the flow-rate (using water meter on cold supply) and it was a lot higher.  I also flooded the bathroom!