Water system replacement with PEX - anyone done it?

[mattlydon]

I am in the midst of repainting my settee lockers after yanking out the horrible, nasty, putrid 35 year old original PVC hose.

I intended to replace the entire system with 1/2 inch PEX. I would have liked to use brass fittings with crimp rings as opposed to quick connectors, as the crimp system seems more secure and a lot less bulky, BUT, looking at them in the store the other day, it appears that in order to fit into the 1/2" pex, the fittings only have approximately 3/8" cross-area inside them.

Is this adequite, or do I need to either go up in size or use quick-connects, which at least seem to be full-flow?

I intend to install a pressure pump, cockpit shower, etc. and don't want to choke it with inadequite feed.

TIA,

Matt

[Steve Laume]

The original plumbing, Cape Dory installed in the pressure systems is not even 1/2" and there are additional restrictions. I don't believe the intermittent joints would cause any noticeable restriction in the water flow.

I have thought about ripping everything out and redoing it all in Pex but I have enough to do right now, Steve.

[Maine Sail]

I am in the midst of repainting my settee lockers after yanking out the horrible, nasty, putrid 35 year old original PVC hose.

I intended to replace the entire system with 1/2 inch PEX. I would have liked to use brass fittings with crimp rings as opposed to quick connectors, as the crimp system seems more secure and a lot less bulky, BUT, looking at them in the store the other day, it appears that in order to fit into the 1/2" pex, the fittings only have approximately 3/8" cross-area inside them.

Is this adequite, or do I need to either go up in size or use quick-connects, which at least seem to be full-flow?

I intend to install a pressure pump, cockpit shower, etc. and don't want to choke it with inadequite feed.

TIA,

Matt

Matt,

The ID is MORE than adequate and infact you could get away with 3/8" PEX and be fine. Remember the 12V pumps can only develop about 25-40 PSI..

I prefer the Watts plastic quick connect fittings .The brass Cash Acme "Sharkbite" fittings just tend to tarnish and looks like crap quite quickly. These quick connects are certified for behind wall installations in residential plumbing where street pressures can exceed 100 PSI. With a crimp you're done, and it's rather final, with a quick connect you can twist the fittings to line stuff up and remove and re-install them. I have them on my water system and remove the manifold each winter. This is going on four years now still re-using the same quick connect fittings.

3/8" PEX is considerably easier to work with on a boat but the fittings and pipe are much less available. Don't be fooled into the "marine" versions of PEX the company is owned by Watts..

If you use 1/2", 10 foot sticks are easier than the coiled bundles. Lowes sells the plastic Watts quick connects and straight 10 footers though not in red/blue only white..

If you go PEX and quick connect be sure to buy a good quality PEX tubing cutter it makes all the difference and they are fairly inexpensive.

[Numbah134]

I've been using PEX in a lubberly application and see no appeal to the crimp connections .vs. a pair of good stainless steel hose clamps over a standard barb. Mostly looks like a scam to sell people a $75-100 crimper where a screwdriver or nutdriver they already own would work as well and be reversible.

I guess I'll take a closer look at the Watts fittings based on what Maine Sail says about them. But my heating system is doubled opposed hose clamps over barbs and I see no problem with that system.

[mattlydon]

It was a snap (pun intended). Had the whole thing done in about an hour. The fittings are a bit painful on the wallet, but very quick. My biggest hitch was tying in to the whale foot pump, which requires 5/8.....

Thanks,

Matt