Posted by john on November 28, 2008, 6:37 am
Someone on one of these forums suggested a while back that I use Wirsbo
brand PEX because of its superior ability to handle heat and pressure
compared to some of the other brands. The tools required to work it
seem a bit pricey and I was wondering if anyone here had anything to
offer in the way of experience, advice, and/or suggestions. The specs
on the product look good, but I'm a little confused on the tools
required to install it. Presumably the hand expander tool is adequate
for a homeowner. How does the tool work and how tight can the pipe bend
(probably 1/2" and 3/4".)
[Sorry if this is approaching "off topic" status, but I do plan to use
it in a solar thermal system, so it is kinda' sorta' related.]
Posted by Rip on November 28, 2008, 1:23 pm
John, years ago I installed radiant heat in parts of my home using
polybutylene tubing. Recently, I added radiant heat (under the existing
floor)using 1/2 inch Wirsbo PEX. In both cases I used standard brass
compression fittings with brass tube inserts, rather than the grossly
expensive fittings requiring special tools that are touted by Wirsbo.
I haven't had a leak in almost 20 years on the polybutylene, and I don't
For the 1/2 inch PEX, if you work carefully you can expect to bend it
around an 8 inch curve (4 inch radius).
Just my $.02 worth.
Posted by john on December 2, 2008, 5:16 am
Posted by Robin Solar on December 2, 2008, 7:09 pm
I have burst Wirsbo on a pumped evacuated tube system when the power
was off and the panel heated excessively. This caused the brass/pex
connection to overheat and the Pex softened, expanded and burst.
Selective coating systems ( flat plate or evac tube ) can overheat
these ratings, so only use them downstream of the storage tank and not
between the panel and tank.
Posted by Rip on December 2, 2008, 10:56 pm
Robin Solar wrote:
Robin, I'll second that. I added more radiant flooring to my house
because I've installed a pretty grossly over-engineered solar hot water
system (5 AET flat panels, 3 Steibel Eltron SB400+ storage tanks).
During Thanksgiving day, I finally filled the collectors with glycol and
turned the system on. It scared the hell out of me! Late November in
Connecticut, and the collectors stagnated at 205 degrees Fahrenheit!
Most definitely not a place for plastic pipes!