Pressure Water Plumbing - PEX, etc.

[Celestialsailor]

Keep in mind there is more to PEX than just the tubing and collars. The manifold you see in my picture I posted would be an excellent way to regulate the tanks. In the past plumbing up my former boats, I sealed off those damn deck fills and plumbed a hose bib into a manifold and filled directly from a hose. I still had access to tank fills inside the boat if I gerry jugged it.

[thefilthywhore]

Originally Posted by Christian Van H

Hey Joey! (notice I used your real name) I was planning on using the PEX variation with the stainless crimped clamp ring and ALL brass fittings. Is their any reason grounded in fact this isn't a viable system for yachts? I havent heard much bad about any of the crimped systems. As for your upcoming hydronic install...I had no idea that PEX was suitable! I am reinstalling a webasto 2010 system in my 42 footer, and would love to use PEX instead of "heater" hose. If this is based in fact, this is GREAT news! Thanks, Chris

Chris,

while I have not seen the crimped style pex fail in home instalations, I would not use them in a marine environment. half of the reason for using pex is to get away from all of the hose clamps, which we all know are prone to failure. the crimp rings are just a single use hose clamp. before installing in my boat I tried to pull the fitting out of the pipe, but could not get a good enough grip onthe pipe to acheive this. I did make a mistake with my last brass threaded fitting and ended spending the better part of an hour cutting the pex off of the fitting.

wirsbo makes a pex pipe specifically for hydronic heating systems along with manifolds and just about everything else you may need to adapt a webasto or espar hydronic heater. the fittings are the same for both aquapex, or hydronic pex, either machined brass or plastic.

keep in mind that the wirsbo pipe is diferent than the other manufacturers, wirsbo is designed to be expanded, where the others are not.

someone else had a question about the temp during install,I dont know what the manufacturer recomends,but in practice I have seen wirsbo installed in temps ranging from 18f-90f without any problems.

hope this helps

joey

BTW my handle is the name of my boat, which has only brought me good fortune. she just likes to be talked to a little dirty.

[Christian Van H]

Originally Posted by Doghouse

I am honestly thinking about replacing them with double hose clamps.

Hey Dog! Thank you for that. I am still leaning toward the copper rings, but I'm going to investigate the Wirsbo this weekend. As for the double hose clamps, I have been told that they CANNOT impart the necessary clamping pressure with PEX. This could be wrong though...but the fittings I have seen wont allow two hose clamps side by side anyway...

Gord, Thanks for that heads up! I have seen that mentioned, and I would love to use PEX for hydronics...

[Cheechako]

I've been considering something like Whale slip fit for a plubing re-do now inthe works. But at $4.50 to $8 a fitting, and after reading all the above.... whats so hard about a nice brass barb and poly tube? Old school.....

[Christian Van H]

That Whale stuff is for the rich! (I think it might be made with real whales...) The stuff I'm looking at averages about 30 cents a fitting!

[Celestialsailor]

Originally Posted by Christian Van H

That Whale stuff is for the rich! (I think it might be made with real whales...) The stuff I'm looking at averages about 30 cents a fitting!

Obviously meant for the top 5% of the wage earners...he he he...(See Global Collapse Destinations Thread)...I crack me up!

[James S]

Originally Posted by Christian Van H

Hi All! I'm getting ready to replumb my boat with PEX and I was wondering what size hose is most common for general pressure water plumbing? I figure most yachts are plumbed with either 1/2" or 3/4" ID hose... also, if anyone out there has used PEX, do you recommend the stainless clamp type, or the copper ring compression clamps for the fittings? Right now I'm leaning toward the stainless clamps. Thanks, Chris

I'm not sure if we're talking about the same stuff...the pipe has an aluminum core?
The stuff I used was very easy to deal with, ,,,the fitting uses a sort of split farrell over the pipe with a nut to compress it, the pipe slides over a male nipple with 2 o-rings.

The fittings are all plated brass and a little pricey.
A friend and I spent two days….. the hole boat was plumbed including a couple tank vents as well.

[Christian Van H]

No core at all James. Not on any I have seen. None of the systems I've seen have compression fittings either...all use some form of clamp or assemble by stretching the hose over the fitting and letting it return to original shape. Nice lookin' stuff there though...Looks like its for the rich!

[TAREUA]

I work in plumbing wholesale (not selling anything here mind you) and would definately go with Wirsbo (Uponor) pipe and fittings. Zurn pex also is a good product, which has one of the better crimp ring systems. Either outfits tool will work for 1/2 thru 1" pipe, though the zurnpex tool will be significantly cheaper and easier to store. The same tool will work for hepex (hydronic) or aquapex (potable) tubing. I have used wirsbo on my boat, and would not use sharkbite type fittings other than as a temporary fix. For that sort of situation they are great and many repair plumbers swear by them. I am not an engineer, but I believe the wirsbo pex sleeves would be much more tolerant of vibration than a metal fitting. They become a point of strenght rather than a point of weakness. One thing to remember is once put together they are not easily disassembled like a hose clamp system.

[GordMay]

Originally Posted by TAREUA

I work in plumbing wholesale (not selling anything here mind you) and would definately go with Wirsbo (Uponor) pipe and fittings... ... The same tool will work for hepex (hydronic) or aquapex (potable) tubing...

Thanks for the advice TAREUA.
Perhaps you could expand upon the differences between Hydronic HePEX+ (/w oxygen diffusion barrier) and the Potable AquaPEX; and why we might select one or the other.
Thanks,
Gord

[Christian Van H]

I did a little research on Uponor (Wirsbo) tools and connections. It really does look like a great system for use in boats. The fittings (valves, elbows, etc.) can be had in brass or plastic, and the connection is made by stretching both the hose and a plastic collar til' they can fit over the connector. The hose and collar then return to normal size, and make a REALLY tight fitting connection. The tool can be had on ebay for $100 thru $500 depending on features. Next we have to find a cheap online dealer that sells SMALL quantities of fittings and pipe. Ohhhhhh...pretty blue for the cold water, flashy red for the hot, and black? for the hydronic webasto system on the boat. I'm gonna have some sexy plumbing!

[TAREUA]

The Hepex tubing has a barrier to protect heating components (ferrous ones) in a radiant system that can be damaged by oxygen. So if you are using pex for a regular hot/cold pressure water system, you can just use the standard (cheaper) aquapex. My understanding is that you can use non barrier pex in heating applications that do not have ferrous components, or in systems where those components are protected by a heat exchanger. My knowledge is however based far more on Wirsbo (now Uponor) reliability than on chemical or engineering know how. I could easily get over my head on technical matters. Most plumbers that I deal with now use almost all plastic fittings (tees, 90's, etc) as they are considered more immune to aggressive water situations. Brass fittings are only favored for threaded fittings where you would transition from pex to screwed fittings.
While I'm rambling, I would also agree with Celestial on the use of a manifold. A manifold can be set up just like an electrical panel complete with individual shut offs for each outlet or inlet and will improve overall flow. You can have a hot manifold and a cold manifold and everything labeled clearly as to what goes where.

[James S]

I didn’t use a manifold... plumbed her pretty much like a house.
However I don’t have the possibility of isolating, but I used the best material I could find and think the possibility of a failure is low and I do have all spare components on board to repair.
I think a manifold may be a good idea but it may require considerably more pipe.

[thefilthywhore]

A manifold is not a necissary component, but is a luxury.

I keep hearing about needing to keep spares and having to repair the potable water piping. this is one of the main reasons I went with wirsbo. the only way I see it needing repair is if the pipe is run up against a moving part ( like a flywheel ). I ahve tried to smash a wirsbo fitting with a hammer, pull the pipe off of a fitting, and generally try to make it fail, all with no effect other than peeling skin off of my knuckles.

I do see a benefit to carrying a wirsbo tool, they work great for expanding hose before inserting a barbed fitting for those applications where it is impractical to use wirsbo. but the wirsbo aquapex and hydronic pex is bulletproof.

one more thing to add to those of you who are considering installing sharkbite or any other fitting with an O-ring, DO YOU REALLY WANT TO TRUST YOUR ENTIRE DRINKING WATER SUPPLY TO AN O-RING?

Joey

[TAREUA]

Another few things to remember. Pex doesn't like sunlight so store unused tubing in a protected spot, and use something else for any on deck or dockside application. While the tubing is extremely durable you want to be careful about transitions thru bulkheads where vibration or shocking from high pressure pump can make the pipe jump if not secured properly. These wear spots can easily be proteced with inexpensive insulation clamps. One last thing is if you need to remove the pipe from an insert fitting (say a welded tank fitting) for any reason, the technique the plumbers use is to carefully cut off the ring, and then gently heat the pipe to allow it to be pulled off. This will keep you from nicking the fitting you need to reuse.