Insulated flow & return pipe recommendations

[JamesPa]

41 minutes ago, JohnMo said:

Wasn't convinced the commercial twin pipe was that good, that's why I did my own, each pipe in its own 110mm duct with 25mm wall thickness insulation all around. Also penny's in the pound cost wise.

 

So only has approx 15mm insulation horizontally. Although there is quite a bit vertical, think the losses would just go sideways.

Indeed, I had the same thought.  Also the min bend radius of the commercial pipe is horrid.

[JohnMo]

2 minutes ago, JamesPa said:

Also the min bend radius of the commercial pipe is horrid.

Flexible 110mm duct isn't too bad, still big but better. I just did a shallow U shape, so I can vertical up the walls and a 90 Deg elbow to take me through the wall.

[Nick Laslett]

Quote

 

@JohnMo 

 

As a side note Hep2O is only happy with 1.3m/s for hot water.

 

 

Should I be worried about this? I assume this is for 60°C water? I’m using Hep20 for my ASHP from the insulated Pex to the UFH manifold. 
 

 

Not sure if I’m using the calculator correctly, but just wanted to record somewhere the max flow rate for 1.3 m/s velocity. I believe my ASHP is running at 14 l/min. 

[JohnMo]

1 hour ago, Nick Laslett said:

Should I be worried about this? 

No

If you are doing 14 l/min and the limit is close to 32 l/min, you have no issues.

1 hour ago, Nick Laslett said:

1.3 m/s velocity

 14 l/min. 

m/S is velocity 

l/min is a volume flow - so very different units.