ransley wrote:


Clark, I see it as rated for 200f, but the site also says " for saftey
and conservation 140F". He can of course do it but it does fail, its
plastic. Radiant underfloor heating is around 110f and lower pressure
than a 185f boiler. My car is rated 5000 rpm redline, , but for long
life it never goes there. Metal is proven, Pex does not have a long
track record in years. nobody really knows how Pex will last at high
temps and pressure over 50 years++.



I don't understand the comment about underfloor heating running at a
different pressure. It typically uses 12 PSI just like other hot water
heating systems.

PEX has been in use for over 50 years. Cross linked polyethylene is a
well proven material.