View Single Post
  #9   Report Post  
posted to rec.boats.building
RW Salnick RW Salnick is offline
external usenet poster
 
First recorded activity by BoatBanter: Jul 2006
Posts: 101
Default anyone used PEX tubing for boat plumbing?

Glenn Ashmore inscribed in red ink for all to know:
"RW Salnick" wrote

When was the Quest stuff invented? My 1978 Downeast 45 is plumbed with
it...



Modular plastic piping systems first came out in the mid '70s. It has had a
rather checkered past. We started using it in '79 in our apartments because
copper was so expensive it disappeared every time a unit went vacant. The
first installations caused a lot of problems. Part of the problem was
improper assembly by plumbers more familiar with sweat jointing copper.
Then there was the infamous problem with polybutylene tubing that was to
soft to hold the fitting clamps. The early Qest pipe was polybutylene and
there were a couple of class action lawsuits about it. As long as the
pressure doesn't get to high it is fine but I would not leave it connected
to shore water when you are off the boat. I think Qest uses cross linked
polyethylene tubing and polybutylene fittings now.

Polybutylene piping in the US has been replaced with PEX cross linked
polyethylene. It holds up much better and the fittings have gotten a lot
more reliable. There are 3 types of connectors: push-on, compression and
clamp rings. The clamp rings are cheaper and more permanent but the crimp
tools run about $150. Push-ons are easier to install than compression but I
suspect that the compression fittings are more reliable.


Thanks Glenn..

No, I absolutely refuse to have my boat connected to city water. There
have been 3 near misses on our dock alone in recent times, where a
fitting of some kind failed inside a boat, and the City of Seattle then
endeavored to sink the boat by pumping in gallons and gallons of water.
In the most recent case, the water level rose over the engine,
requiring an engine replacement, in addition to extensive interior
refurbishment. In this particular case, the owner was aware of the
risk, but promised himself that he would always turn off the city water
when leaving the boat. He forgot. I live off my tanks, thank you very
much.

Sorry, I guess that sounded like a rant.

I have had two failures (tiny splits) of my 28 year old polybutylene
Qest plumbing - both immediately above the water heater where the tubing
is subjected to continuous hot soak conditions. In both cases, I have
replaced the tubing runs with Pex. All the fittings are compression
fittings. They work very well.

bob
s/v Eolian
seattle