In article , chris French wrote:
In message , Alan Braggins
writes
In article , chris French wrote:
In message o.uk, Dave
Liquorice writes
On Thu, 3 Nov 2011 08:11:36 -0000, DIYer wrote:

Also, Screwfix stock a plastic pipe system by FloPlast (Flo-Fit) at a
good price.

Check the temperature and pressure ratings. The pressure rating drops
dramatically as the temperature rises.

Is that likely to be a problem with any of the plastic plumbing systems
though and even a pressurised system is only run at 1 bar or so. Hep2O
and Speedfit are fine.

If you've got mains pressure hot water, that can get a fair bit over 1 bar.
(Without checking the ratings, I don't know if it's likely to be a problem.)

I can't remember now without looking it up, but Hep2O was fine for the
mains pressure water in our old house - and that had pretty high
pressure.

Of course this ha smade me go and look it up :-)
http://www.floplast.co.uk/pages.asp?pageid=43012753&catid=312
for Floplast it gives a max working pressure of 12 bar at 20C
at 85C, 4 bar

Hmm. In the middle of the night when the mains pressure might reach
10 bar in some areas you won't be running hot water through it, and
you won't run your hot taps or shower at 85C. But I think you would
want to be cautious about how close you ran it to a combi boiler or
thermal store heat exchanger.