On Fri, 13 Jan 2006 12:58:29 -0000, "Christian McArdle"
wrote:


19mm isn't a bad bore, but I think I'll stick with the full 22mm. I want
every last litre per minute out of it. Whilst my pressure is reasonable, it
isn't brilliant, as I'm on top of a hill. The softener itself is going to
lose me over 1 bar.

Christian.

Using:

http://www.efunda.com/formulae/fluids/calc_pipe_friction.cfm#calc

30cm of 19mm pipe at 30 lpm gives 0.00577 bar pressure drop
30cm of 22mm pipe at 30 lpm gives 0.00285 bar pressure drop

So there's about 0.00292 bar or 0.042psi in it.

So a good case for using 22mm pipe over long runs but a short run of
19mm shouldn't hurt.

I'd expect the flexis from BES aren't shouldered.

cheers,
Pete.