Best pressure hose for watermaker

[ColdEH]

Looking for opinions on the high pressure side hose of a watermaker.

Is it important to look for a hose that will not leach anything into the sea water? Is there a "food grade" pressure hose out there? Since we are so carefull to make water in clean sea water, you wouldn't want to have your hose ruin your expensive membranes.

Regards .

[ColdEH]

I just did a little research and made a few phone calls, found that hoses lined with a Teflon core are probably the most suitable for a watermaker's needs .

Something like this

316 Stainless Steel Braided Hose with Solid FNPT Ends

Regards

[Cheechako]

Just look up a hose shop like Aeroquip etc and ask them. They will make to a custom length whatever you want.

[Lancerbye]

Originally Posted by typhoon

I just did a little research and made a few phone calls, found that hoses lined with a Teflon core are probably the most suitable for a watermaker's needs .

Something like this

316 Stainless Steel Braided Hose with Solid FNPT Ends

Regards

I have this in my system with reusable fittings. This was installed by the PO and has been a good set up, however I am finding that the SS JIC fittings corrode at the joint between male and female connections and eventually leak. Finding the reusable fittings in SS is somewhat problematic at times. I have been considering using a flex-bendable solid stainless half in. tubing to replace the braided stainless over Teflon. With good quality (Swagelock) compression fittings this should make for a solid system.

[ColdEH]

Originally Posted by Lancerbye

I have this in my system with reusable fittings. This was installed by the PO and has been a good set up, however I am finding that the SS JIC fittings corrode at the joint between male and female connections and eventually leak. Finding the reusable fittings in SS is somewhat problematic at times. I have been considering using a flex-bendable solid stainless half in. tubing to replace the braided stainless over Teflon. With good quality (Swagelock) compression fittings this should make for a solid system.

Good idea, I guess the best SS fittings are in order. The solid pipe would not work for me , my pump is in the engine room and the pressure vessels are under the aft bunk.

Regards

[Lancerbye]

Originally Posted by typhoon

Good idea, I guess the best SS fittings are in order. The solid pipe would not work for me , my pump is in the engine room and the pressure vessels are under the aft bunk.

Regards

The Stainless tubing is solid but bendable and comes in a 3ft. diameter roll so one can snake it through an area if you can kind of unroll it as you position it. To make nice 90 deg. bends or offsets you still need a good tubing bender like an Eastman or Swagelock. This stuff is only found in industrial suppliers like Swagelock. My pump is in the lazarette , with the pressure vessels but has to route to the pressure control which is through the engine room , two bulkheads, on a bulk head under the steps leading down to the Galley and state rooms. I am planning to do this in May. Should be fun.

[ColdEH]

I just realized I should have said my pump is on my generator engine and dances around a bit , so I will have to go with the stainless braid over the Teflon core for its ability to absorb the vibration.

Regards

[SV THIRD DAY]

The best approach here is the teflon line (NSF Drinking water certified) that is covered by a SS braiding to make it "high pressure", and then the SS braiding is covered by a silicone coating for chafe protection. Using swagelok compression fittings on the end of the line makes easy multiple on/off cycles possible without the fear of leaks and the Stainess to Stainless seal of a Swagelok compression fitting is simply not goint to leak or suffer a cracked or lost o-ring. They use these same fittings on high pressure fuel lines (gas/liquid) for turbine engines, where a fuel leak would blow the turbine and people up!

You can use this hose without the silicone chafe cover, but I wouldn't recommend it.



I would recommend the silicone chafe protection! It doesn't cost much more and it can save you form a disaser from a blown line due to chafe.

In terms of price just to give you a feel, we sell a 1ft length of 3/8" hose with the compression nut end fittings attached for $105, then additional length is $10/ft. So a 5ft hose would cost $105 + 40 = $145.

I would go with 3/8", because 1/4" hose just has too much pressure drop, but we have tested a 30ft length of 3/8" Hp hose between the pump and Membranes with ZERO negative measurements.

[ColdEH]

That looks great, I also like the blue matching water like to your tanks

Regards

[SV THIRD DAY]

Originally Posted by typhoon

That looks great, I also like the blue matching water like to your tanks
Regards

We love that stuff compared to the old school braided tygon water line that ages to a nasty yellow petina! We use it for all the low pressure water lines (1/2" for the supply side and 1/4" for the product and brine side). Plus at 1/4" is so damn easy to push and shake through your boat. The manufacturer is GA Murdock for the hose and the push-to-connect fittings. They beat the heck out of those hand cutting hose clamps!

[ColdEH]

Originally Posted by SV THIRD DAY

We love that stuff compared to the old school braided tygon water line that ages to a nasty yellow petina! We use it for all the low pressure water lines (1/2" for the supply side and 1/4" for the product and brine side). Plus at 1/4" is so damn easy to push and shake through your boat. The manufacturer is GA Murdock for the hose and the push-to-connect fittings. They beat the heck out of those hand cutting hose clamps!

Yeah I hate the stuff too ! My Bristol has all copper plumbing on the preassur side , but the stuff from the tanks to the pump is that clear tygon stuff , yuk . Im installing a Head Hunter Mach 5 pump and Im going to pull it out and put in "Watts" stuff, I think its the same as the stuff you are using , so simple.

Regards

[Nauticatarcher]

Aircraft grade hydraulic hose, any hydraulics shop should be able to make it up