[VACList] Re: plumbing with PEX

["jon fitz" <fitzjo1@xxxxxxxxx>]

Hi, Lexxy.  I'm working on my plumbing now, as well. 
Here are some suggestions for you or anyone else (like
me) who collects this sort of info.

I am going to stay with the original layout, more or
less.  I suggest keeping the fill valve, for reasons
already addressed in a previous post.  I have
relocated some of the tees to account for the change
in material (PEX vs. copper).  I don't want a lot of
residual stress on the fittings from tight curves,
etc.

You didn't mention what type of plastic you were going
to use.  I think the PEX is a pretty good idea.  I
would be reluctant to use PVC, just because of the
risk of freeze damage.

I checked with my dad (who is a mechanical engineer
and a licensed plumber) and he gave PEX the OK.  He
doesn't use it often, but says it will tolerate
freezing better than the available alternatives.

The biggest drawback is that you will need to
buy/borrow a crimp tool or use the more expensive
fittings.  If you buy a tool, get a short handled one.
 It's harder to operate, but will fit into tighter
spaces.  I have a MIL3, which is about 10" long.  Some
other models are more like 18".  

I saved 1/2 to 2/3 on fittings by going to a plumbing
supply house. But, don't go there expecting to
browse--these places are typically counter sales only.
 They are set up to work with professionals--not to
educate aspiring plumbers.  You will need to draw out
your plans in detail and work up a complete bill of
materials.  Don't go until you know exactly what you
want.  Fitting selection at most places is limited to
Tees, Ells, Couplings, Plugs, PEX-FPT, PEX-MPT,
PEX-sweat(copper), and valves.  Other variations are
easily created in combination with non-PEX fittings.

Here's one final suggestion.  Install your supply
lines as if they were drain lines.  In other words,
take the time to fasten them in place with a gradual
slope towards the drain valves.  This will make it
MUCH easier to reliably drain the lines in the fall. 
There were low spots all over my original system, and
every one of them was bulged or burst from freezing.

Jon in SC
68 Overlander