PEX plumbing fittings

[seattleboatguy]

I'm getting ready to do some upgrades with my fresh water pressure system, and I'm wondering if I should stick with the old copper tubing I have now or if I would be better off to replace it with PEX stuff. Thanks for any feedback.

 

[FoxtrotCharlie]

I would transition to pex - very easy fittings for this. 1/2" copper? 3/8' copper? In either case, the copper and pex are same exterior size, so sharkbite fittings work great - a bit pricy. If you have the pex crimpers and know how to sweat copper, then skip the sharkbite. Easy to find 1/2" at HD or Lowes, but 3/8" is scarcer - easy online. I moved to 1/2" from the 3/8" that was original on our boat.

 

[ScottC]

I would say go to PEX. My boat was totally fitted from the factory with WHALE tubing (which I think is about the same thing). Red for hot. Blue for cold. Special fittings that simply press on. No corrosion or leaks in the 10 years I've had the boat. I've made several enhancements and the "plumbing" part could not have been easier. They have all manner of adapters available for where you need to hook up with more "traditional" npt or flared connetions.

 

[Bacchus]

Agree go PEX.
It is EZ PZ stuff to work with.
If doing a lot its worth buying the crimp tool vs using all removable push on fittings. The removable ones are OK where you might want to take apart in future but crimp ftgs are a lot less $.
You can use either the solid rings or the cinch type both work well but cinch are a little easier to remove than the rings if you ever have to and a cut off tool also available. Get a tubing cutting tool to cut it square.

 

[Marco Flamingo]

I remodeled my system using Pex-Al-Pex because I had 100' left over from doing a hydronic floor heating system. PAP has a thin layer of aluminum in it and stays flexed when bent. That makes it easy to go around corners (with a radius bigger than about 5 inches) and saves on buying el fittings and wrestling with coiled Pex. Buy a roll, keep 20 feet for possible future mods, and give/sell the rest. Still cheaper than buying sticks at the hardware store.

The new SS crimp rings are so much faster and cheaper than the old copper bands. Same with the crimp tool. Easily removed with an awl if you make a mistake measuring or want to modify. I wouldn't mess with red for hot and blue for cold. Simple enough to label the white or orange tubing with a Sharpie if your system is that complicated.

 

[twistedtree]

PEX-AL=PEX I think requires special compression fittings. I used it for a compressed air system, and it required compression fittings. So I wouldn't go that route unless like Marco, you happen to have a bunch of it lying around.


Otherwise I'd use PEX with compression rings/bands. Or alternately use PEX-A with expansion bands. Whichever you do, it's worth getting the tool(s)

 

[seattleboatguy]

Would you lean more toward plastic or metal fittings?

 

[psneeld]

I used brass for the fresh water system and plastic for the salt water system.both have worked and lasted fine.

I can't say for sure, but the plastic may reduce flow a bit as they may be thicker walled....but I haven't looked up the specs.

 

[Bacchus]

I used brass for the fresh water system and plastic for the salt water system.both have worked and lasted fine.

I can't say for sure, but the plastic may reduce flow a bit as they may be thicker walled....but I haven't looked up the specs.

[emoji106]
Brass Ls & Ts are small and easy to fit in tight spaces and they are strong.
Only issues I've had with p,astic are with female pipe threads onto a male pipe that split the plastic nut. It seems to be the weak link.
It is helpful to do " dry fit" with fittings and tube and then crimp several fittings of a sub- assy.

 

[twistedtree]

Would you lean more toward plastic or metal fittings?

I've used both without concern for fresh water, but you definitely don't want to use brass with salt water.


Also keep in mind that the fittings are different for the expansion fitting system, and are not interchangeable with fittings for a crimp system. Also, only PEX-A can be used with an expansion system, not PEX-B.

 

[Ken E.]

Another vote for Pex. I used the Pex A Uponor system, which uses expanding non-metal rings. The battery-powered expander tool...mine is a Milwaukee....allows you to get into tight spots. Supplyhouse.com has the tubing, fittings and tools. 100% happy with the result.

 

[Marco Flamingo]

I used the copper compression rings for the hydronic floor, but for the potable water onboard, I used the SS crimp rings. The tool was cheaper and smaller, plus it will do 1/2" and 3/4". I don't know what my little Jabsco pump produces for water pressure (30 psi?), but it's a lot less than my air compressor. I did have one leak, but that was operator error with the crimping tool in a tight place and was easily fixed.

 

[twistedtree]

Another vote for Pex. I used the Pex A Uponor system, which uses expanding non-metal rings. The battery-powered expander tool...mine is a Milwaukee....allows you to get into tight spots. Supplyhouse.com has the tubing, fittings and tools. 100% happy with the result.

Same setup I'm using now. On a boat, I like the non-metallic system

 

[FF]

I prefer to stick with copper tubing , use the refrigeration grade if there will be need for complex tubing bends.

Only God knows what leaches out of plastic when the vessel sits unused.

At least with copper it keeps the water fresh , and can be replaced anywhere world wide.

5/8 copper tubing with flair fittings flows well enough to lower the fresh water pressure , saves electric and water.

 

[boathealer]

My boat is 95% push-lock PEX. It has been trouble-free as long as good connection practices are followed.

 

[lwarden]

My boat has the Whale fittings. Unfortunately, they don't use standard diameter PEX tubing, so you need to buy their tubing as well, and both the fittings are tubing are expensive. I've had the Sharkbite push-on fittings leak (o-ring split) when used in my house so I avoid those. If I were to do a boat from scratch I would go regular PEX from Home Depot or Lowes and brass fittings and the SS crimps. Crimp tools and cutters are very inexpensive from Amazon/Ebay. Plastic fittings for any raw water is the way to go, but I would trust the brass ones more for fresh.

 

[rgano]

Pex

 

[Datenight]

Another one for the PEX Uponor system It's what came on the boat and what we did the house with. Bonus to already have the tools.

First shot is the underfloor heat manifolds at home. Next two are the bypass I added to the water heater circuit on the boat. The last one shows the "T" that allows me to draw antifreeze into the freshwater system just before the pump.

Rob

 

[Ken E.]

Youtube has several demo videos of the Uponor system.

 

[AKDoug]

One (small) issue with the pex is that it's not designed to disassemble, so you have to use threaded connectors that will rotate if you plan to disassemble (like for winterization) on things like water pumps. Once the ring is crimped it's pretty much stationary and something else has to be able to turn somewhere in the system if unthreading a fitting is required. It just requires preplanning on things you might want to take apart or replace.

I have a mix of pex and copper compression fittings so I can drain and replace.

 

[Ken E.]

One (small) issue with the pex is that it's not designed to disassemble, so you have to use threaded connectors that will rotate if you plan to disassemble (like for winterization) on things like water pumps. Once the ring is crimped it's pretty much stationary and something else has to be able to turn somewhere in the system if unthreading a fitting is required. It just requires preplanning on things you might want to take apart or replace.

I have a mix of pex and copper compression fittings so I can drain and replace.

I used the male and female version of these for my galley and heads re-do. PEX on one side of the fitting, pipe threads on the other. Worked well hooking up to fixtures and for draining, if necessary. But your point is true, something has to be able to rotate at the threaded connection.

https://www.supplyhouse.com/Wirsbo-...Brass-Male-Threaded-Adapter-1-2-PEX-x-1-2-NPT

 

[AKDoug]

I did too, as well as compression fittings where it was too hard to tear out and replace the copper lines. It just bears thinking about when you do the job.

 

[koliver]

One (small) issue with the pex is that it's not designed to disassemble, so you have to use threaded connectors that will rotate if you plan to disassemble (like for winterization) on things like water pumps. Once the ring is crimped it's pretty much stationary and something else has to be able to turn somewhere in the system if unthreading a fitting is required. It just requires preplanning on things you might want to take apart or replace.

I have a mix of pex and copper compression fittings so I can drain and replace.

Or T in a dedicated drain line with a valve.

 

[Bacchus]

One (small) issue with the pex is that it's not designed to disassemble, so you have to use threaded connectors that will rotate if you plan to disassemble (like for winterization) on things like water pumps. Once the ring is crimped it's pretty much stationary and something else has to be able to turn somewhere in the system if unthreading a fitting is required. It just requires preplanning on things you might want to take apart or replace.

I have a mix of pex and copper compression fittings so I can drain and replace.

Thats exactly the reason why I replumbed the ,as boat with PEX to eliminate the need to take apart fittings and add bypasses. It seems most times they leaked when reinstalled they leaked. Design the system with 3 way valves to bypass drain and add AF and no leaks!

 

[DennisB1]

I have pex on my 1990 GB. Still in good working order except for two leaks. They used aluminum crimp rings. In one location the aluminum rings were touching the copper ground strap. 25 years later they broke at the contact points with the copper bond strap and weeped. Replace the tubing installed new copper crimp rings in that location -- no more leaks.

 

[amapola]

Ditto PEX

 

[Ralsy]

Just something I found online. Not sure if it's a slightly biased opinion as it's from a plumbing business.
PEX failures

Piping fails when the pipes are exposed to chlorine that is within the water, exposure to direct sunlight before its installation. Furthermore PEX pipe is vulnerable when it comes in contact with such solutions as petroleum products and oxygen. It can leach toxic chemicals from pipe material also.May 27, 2017
www.repipeyourhouse.com › pex-pl...
Pex Plumbing Failures - Super Mario Plumbing

 

[EngNate]

It's a landslide, but one more vote for pex. It's hard to justify if the tool costs you more than the project, but the expansion system is so much easier and faster to work with than the crimp. You expand the end and then have about 20 sec to slip it over the fitting, so you don't have to work right in a tight corner. The joints can be disassembled by softening the tubing and ring with a heat gun. You can get rings in red, blue and white, an option to buying 2 or 3 colors of tubing.

The above mentioned article (Kitex Warning, at the bottom of the home repiping page) refers to a pipe and fittings by manufacturer IPEX, not PEX tubing, which is made by several manufacturers.

 

[Hawkshaw1]

Another one for the PEX Uponor system It's what came on the boat and what we did the house with. Bonus to already have the tools.

First shot is the underfloor heat manifolds at home. Next two are the bypass I added to the water heater circuit on the boat. The last one shows the "T" that allows me to draw antifreeze into the freshwater system just before the pump.

Rob

What a nice neat job on your boat!

Hawk

 

[Datenight]

What a nice neat job on your boat!

Hawk

Thanks, most important part of the job is the planning. Did a few drawings before cutting pipe.

Rob