I installed this hose when I converted my hand pumps to pressure water 25 years ago (3/4") and overall it has served me well, but there have been, over those years, 4-5 pinhole pressure leaks that I have had to repair, cut out and install a connector, etc. This stuff is stiff, thick walled, hard to cut, must be heated with hair blower or boiling water to fit onto a 3/4" repair barb. So today, after another pinhole leak, I do some research and find Shields states "not for pressure water systems". Either they did not state this years ago or I "missed the boat" on this one back then (pun intended). If I decide to pull that out of there, what should I be using?
Shields VAC XHD 148 hose
- Thread starter odaydokay
- Start date
Trident has hoses specifically for hot and cold fresh water plumbing Potable Water Archives - Trident
Shields--and also Trident-- #148 are rated for use in a sanitation system, but are so susceptable to odor permeation that you don't want to use it for that either.
--Peggie
Shields--and also Trident-- #148 are rated for use in a sanitation system, but are so susceptable to odor permeation that you don't want to use it for that either.
--Peggie
Hopefully staying inline with the original poster’s title, Peggie I have 2 questions about the Shield VAC XHD 148 hose.
1. Recently the 3/4” water (salt) intake hose (Shields 148) for my manual toilet developed a split right at the pump barb fitting. I was able to cut the hose off at the split and put it back on the barb but there is no stress relief at all now. I need to replace that hose or it’s just a matter of time when I have a bigger problem.
2. I replaced the galley sink drain hose with 1 1/4” Shields 148 hose about 3 years ago. I now see in specs that the 148 has a maximum temperature of 120 deg F. Often we put boiling water down the sink drain and would like to change that hose also. Obviously there is no pressure but it does drain below the waterline on its own thru hull and therefore will have a foot or so of saltwater in the lower end at all times.
Neither Raritan Saniflex nor Trident 101/102 are available in either 3/4” or 1 1/4”.
I would appreciate it if you could recommend replacement hoses for each application?
So no recommendation for my 3/4"
Many thanks, Peggy!!!!!!!!!
pressure (fresh) water system if i decide to replace?
Many thanks, Peggy!!!!!!!!!
I’ll have to do a little more researching when I have reliable data service.
HB I had to click on the various hoses to get the data regarding their use as "below water line" use. Some said "NO!" (NOT RECOMMENDED FOR BELOW WATERLINE THRU-HULL CONNECTIONS) others did not specify "below water line" use. Finally I found a "rubber hose with reinforcing" Trident Ocean-Flex – #321 that specified "Water (Vital and Non-Vital)". I suspect "vital" addresses "thru hull" usage. It meets a number of CG standards for commercial/recreational use.
All this research makes me wonder if I used the right hose on my recent install. I thought I knew what I did not know.
Boat US provides this information regarding selection of a "Thru Hull hose"
Even the proper hose lasts only so long — this hose is past due for replacement.
All this research makes me wonder if I used the right hose on my recent install. I thought I knew what I did not know.
Boat US provides this information regarding selection of a "Thru Hull hose"
Through-Hull Hose: Strength
Even the proper hose lasts only so long — this hose is past due for replacement.
Stiff hoses can be easier to install if the end is dipped in very hot water for a minute; this allows the end to stretch more easily.
Through-hull hoses are really just an extension of a hole in your boat, the above- or below-waterline fitting to which they are attached. As such, any through-hull hose must be exceptionally strong and long-lasting, and designated as suitable for use below the waterline; look for a label on the hose itself or wording in the manufacturer's description. Water-intake hoses also need to be rigid enough to withstand suction from the pumps. Hoses that attach to through-hulls are typically made from rubber and reinforced with metal or plastic spirals. They should not be bent at too tight an angle or the hose will be weakened. Two-ply pickup hose intended for use in wet exhaust systems can be considered the gold standard for raw-water intake hose. Where heat is not an issue and some flexibility is required, extra-heavy-duty smooth vinyl hose with a hard PVC helix can be used. The lifespan of these hoses varies with their job, but after 10 years, consider them all suspect.
So I need 22' of something like a Shields 162 or similar reinforced PVC, but everyone either wants big $ per foot or a fair price for a 50 or 100 foot roll. Anyone got any ideas?
Is it possible to change the barbs in your system to something else? I mean, are the barbs that the hose goes on threaded into an NPT fitting?
By the way, I hate that stuff! My Catalina 36 used that kind of hose for the water system, and it was maddening to connect and disconnect; it got hard with age; leaks were hard to stop; and so on. That's why I asked if you could change the barbs out: I was going to suggest a different tubing system.
About 10 years is the average lifespan of any hose because rubber and plastics dry out, 'causing 'em to get hard, brittle and prone to cracking or splitting....a different tubing system unless it's copper or hard pvc (I don't think either are recommended for fresh water plumbing on a boat) won't last any longer. A split fresh water system hose isn't likely to sink a boat, but it can make a major mess...old hoses connected to open below-waterline thru-hulls are one of the leading causes of boats sinking in their slips (flush water intake thru-hulls left open to a toilet that doesn't have a vented loop installed in the intake is another one).
--Peggie
--Peggie
Peggy, where do you get this from, do you have any references for this lifespan for tubing? Ten years is absurdly low for most plastic plumbing products. Note that Pex has overtaken copper in residential plumbing systems, and its expected service life exceeds 50 years. Just looking quickly one finds this, for polyethylene pipe: "Interim report findings state PE pipe can last in excess of one hundred years under most water quality conditions, service environments and disinfection techniques. “One hundred year service life exceeds typical expectations; fifty years is widely accepted as the usual benchmark” explained Tony Radoszewski, executive director of the PPI." https://plasticpipe.org/pdf/press-release-jana-lab-tech-report.pdf
I don't know anyone who's had to rip-out and re-do ten year old plumbing of any kind in a boat. My polybutylene tubing in the '96 Tartan is fine, no signs of impending failure, at all. I'm sure we'd be hearing about it if boat plumbing was failing all over the place. For new work I'm using LLDPE, which is extremely common in food-grade tubing applications in plants, restaurants, etc.
As far as copper is concerned, it is not immune to failure, particular at joints, and pinholes due to internal and external corrosion. I don't know anyone with copper plumbing on their boat.
The 10 year average lifespan for all hoses is what I've been told by several ABYC certified marine mechanics and NAMS certified surveyors. That it's not falling apart after 10 years doesn't mean it hasn't gotten hard and brittle.
--Peggie
--Peggie
Thanks. It would be useful to drill down to specifics, like, what kind of hose, tubing, etc.
This turned out to be a winner. Just got it delivered, price was freight prepaid even. As for discussion about hose longevity, it probably helps to start with the correct stuff in the first place.....which I apparently did NOT!
My 1996 boat's original polybutylene tubing plumping is still as good as the day it was installed. This stuff was controversial in homes, and there were lawsuits, etc., over tubing failures. I don't know all the details. But in my boat mine is intact, and the Parker O-Ring Grab-Ring fittings are near perfect. For new routes and mods I'm using LLDPE (Linear low-density polyethylene) tubing, which is the same O.D. and food grade, and the same connectors.