On 2008-08-02 13:13:51 +0100, "Steve" said:

Hi

I'm going to be using quite a bit of (22mm and 15mm) plastic barrier pipe
for central heating and wondered if anyone can advise on the following.

Q1. I used a coil of Speedfit a few years ago and it was a bu**er to work
with because it was so springy and wanted to return to its coiled shape.
Are coils of other makes any better in this respect (I have Hep2O and
Equator in mind)?

Not really. Warming it can help a little but a better solution is
just to buy straight 3 or 6m lengths.





Q2. Presumably the different makes have slightly different internal
diameters. I calculate that if an internal diameter increases, for example,
from 11mm to 13mm then the internal cross-sectional area increases nearly
40% (area being proportional to diameter squared). This would give a
significant reduction in resistance. Are any of the available barrier pipes
of significantly greater internal diameters than their competitors?

They are supposed to be standard according to the BS specs. The
critical thing is to use the inserts that relate to the fittings as
these are not interchangeble between brands

Finally, it is advised to use a proper tube cutter and not a hacksaw
for cutting the tube in order to retain system continence and your
reputation.