Reply
 
Thread Tools Display Modes
 
Old 02-27-2015, 08:25 AM   #1
Member
 
billwilletts's Avatar
 
City: Southport NC
Country: USA
Vessel Name: Jolly Mon II
Vessel Model: Marine Trader 40 Double Cabin
Join Date: Sep 2012
Posts: 8
Polyethelene pipe, MPDE or HDPE for sanitation lines?

Has anyone every used poly pipe for waste lines? It is made from polyethelene just like the tanks so I am wondering why it isn't more mainstream on boats? It appears many European boaters have adopted it. Your thoughts?
__________________
Advertisement

billwilletts is offline   Reply With Quote
Old 02-27-2015, 08:50 AM   #2
Guru
 
No Mast's Avatar
 
City: Atlantic Highlands, NJ
Country: US
Vessel Name: Moana Huaka'i
Vessel Model: Selene 53
Join Date: Dec 2014
Posts: 816
We will be pulling into a yard near Charleston next week for some tasks. One of them is replacing sanitary hoses and addressing a shortcoming in the holding tanks initial design. We are replacing the lines with PVC.
__________________

No Mast is offline   Reply With Quote
Old 02-27-2015, 08:53 AM   #3
Member
 
billwilletts's Avatar
 
City: Southport NC
Country: USA
Vessel Name: Jolly Mon II
Vessel Model: Marine Trader 40 Double Cabin
Join Date: Sep 2012
Posts: 8
I would think that PVC would be ok too provided there are some flexible hose at stress points right?
billwilletts is offline   Reply With Quote
Old 02-27-2015, 08:54 AM   #4
Guru
 
Rogerh's Avatar
 
City: Niceville, FL
Country: USA
Vessel Name: At Last
Vessel Model: 1990 Jefferson 52 Marquessa
Join Date: Aug 2013
Posts: 665
When I did all of mine last year I replaced a fair amount with PVC. I don't know about using the others that you mentioned. No experience there.
Rogerh is offline   Reply With Quote
Old 02-27-2015, 08:57 AM   #5
Guru
 
No Mast's Avatar
 
City: Atlantic Highlands, NJ
Country: US
Vessel Name: Moana Huaka'i
Vessel Model: Selene 53
Join Date: Dec 2014
Posts: 816
PVC's major advantage is it will not permeate, basically ever. All other flexible hoses will eventually. From what I've been reading on it seems when it comes to any flexible hose the thicker it is the longer it will remain smell free.

Yes the disadvantage of PVC lies in its rigidity, and that needs to be carefully evaluated to ensure there are no stress points
No Mast is offline   Reply With Quote
Old 02-27-2015, 08:58 AM   #6
Guru
 
Rogerh's Avatar
 
City: Niceville, FL
Country: USA
Vessel Name: At Last
Vessel Model: 1990 Jefferson 52 Marquessa
Join Date: Aug 2013
Posts: 665
Yes, you want some flexible hose to allow for movement. I found that some places PVC just would not work. In those areas I used a very good quality marine head hose. Also need to use special fittings to go between the PVC and hose. You can get them at:
PVC / Fittings
Rogerh is offline   Reply With Quote
Old 02-27-2015, 09:09 AM   #7
Member
 
billwilletts's Avatar
 
City: Southport NC
Country: USA
Vessel Name: Jolly Mon II
Vessel Model: Marine Trader 40 Double Cabin
Join Date: Sep 2012
Posts: 8
Roger that is what intrigues me about the poly pipe. It is flexible but also impervious to smells (at least for many many years) just like the holding tanks. Seems like it would be the best of both worlds?
billwilletts is offline   Reply With Quote
Old 02-27-2015, 09:18 AM   #8
Guru
 
No Mast's Avatar
 
City: Atlantic Highlands, NJ
Country: US
Vessel Name: Moana Huaka'i
Vessel Model: Selene 53
Join Date: Dec 2014
Posts: 816
For me it's that, many years part that. We plan on having Moana for many years. I'd rather not have to deal with the issue again later. With PVC I shouldn't.
From what I understand it's in the nature of what makes a hose flexible that allows it to permeate, so all flexible hose will eventually. Comparing hoses of the same material, the thicker the hose the slower it will permeate.

Some Selenes have a rep as smelly boats. We believe to have found out why and are addressing what we feel is a flaw in the holding tank. And we are hedging our bet by using PVC.
No Mast is offline   Reply With Quote
Old 02-27-2015, 10:11 AM   #9
Guru
 
Join Date: Aug 2012
Posts: 741
I replumbed with rigid PVC seven years ago. Added water traps to both heads and converted the old Raritan heads to fresh water flush at the same time. Zero odor issues to this day. Used flex hose from farm dairy/milk bulk tank installation for the connections. Make sure the system is designed so that there are no up hill points in the hard line runs to the tank(s)...fairly easy with risers just after the bowl (to keep water in the bowl).
Underway is offline   Reply With Quote
Old 02-27-2015, 11:13 AM   #10
Senior Member
 
obthomas's Avatar
 
City: Seabrook Texas
Country: USA
Vessel Name: TheVenture
Vessel Model: 1985 Bestway Labelle Sundeck 40ft
Join Date: May 2013
Posts: 462
I think the biggest problems with PE pipe is fittings. Most of the MDPE and HDPE I have seen uses welded fittings and flanges that permit adapting to other fittings. The plastic welding machine requires factory training to use. So how is everyone connecting this stuff?
obthomas is offline   Reply With Quote
Old 02-27-2015, 12:12 PM   #11
Guru
 
No Mast's Avatar
 
City: Atlantic Highlands, NJ
Country: US
Vessel Name: Moana Huaka'i
Vessel Model: Selene 53
Join Date: Dec 2014
Posts: 816
The question of connections for us will be settled after we are at the yard and determine the location for each connection, and what we are joining between.

Where the outflow from the heads enters the holding tank is being moved. We have some flexibility as to where to move the connections to, and I'd like to create as long a straight inclined run with the PVC as possible, but still need to discuss this in more detail with the yard. They have actually done this same modification to other Selenes before with great success.
No Mast is offline   Reply With Quote
Old 02-27-2015, 02:58 PM   #12
Member
 
billwilletts's Avatar
 
City: Southport NC
Country: USA
Vessel Name: Jolly Mon II
Vessel Model: Marine Trader 40 Double Cabin
Join Date: Sep 2012
Posts: 8
Ok so here is another obvious choice - flexible PVC pipe - like they use on pools and hot tubs? It is all PVC but also flexible and the standard PVC fittings will glue right up. It looks just like sanitation hose too. PVC won't absorb smells either.
billwilletts is offline   Reply With Quote
Old 02-27-2015, 03:13 PM   #13
Guru
 
No Mast's Avatar
 
City: Atlantic Highlands, NJ
Country: US
Vessel Name: Moana Huaka'i
Vessel Model: Selene 53
Join Date: Dec 2014
Posts: 816
From what I've learned, once a hose is flexible, it will eventually permeate.
No Mast is offline   Reply With Quote
Old 02-27-2015, 03:21 PM   #14
Guru
 
Rogerh's Avatar
 
City: Niceville, FL
Country: USA
Vessel Name: At Last
Vessel Model: 1990 Jefferson 52 Marquessa
Join Date: Aug 2013
Posts: 665
Bill, I removed about 20 feet of the flexible spa PVC hose. It stunk so bad that I thought I was going to loose 50 lbs removing it. Believe me it does permeate and this was only 5 yrs old. From my experience I would never use it.
Rogerh is offline   Reply With Quote
Old 02-27-2015, 03:25 PM   #15
Guru
 
No Mast's Avatar
 
City: Atlantic Highlands, NJ
Country: US
Vessel Name: Moana Huaka'i
Vessel Model: Selene 53
Join Date: Dec 2014
Posts: 816
Roger: must have been a big lunch.

Bill: When it comes to flexible hose, besides only using sanitation type hoses obviously, the thicker the hose is the longer it will take to permeate. But eventually it will.
No Mast is offline   Reply With Quote
Old 02-27-2015, 03:33 PM   #16
Member
 
billwilletts's Avatar
 
City: Southport NC
Country: USA
Vessel Name: Jolly Mon II
Vessel Model: Marine Trader 40 Double Cabin
Join Date: Sep 2012
Posts: 8
Wow that is surprising so maybe there is something to the flexibility that allows it to permeate. I might look at the pvc route too now - they have flexible couplings you can purchase so that might be a good long term fix. Interesting idea too about the trap - I guess the principle is the same as a house - it blocks the smell. Not sure I have room to do that though.
billwilletts is offline   Reply With Quote
Old 02-27-2015, 03:42 PM   #17
Guru
 
No Mast's Avatar
 
City: Atlantic Highlands, NJ
Country: US
Vessel Name: Moana Huaka'i
Vessel Model: Selene 53
Join Date: Dec 2014
Posts: 816
It gets into technical specifics that are beyond me but I've read in more than one book, had explained to me by a few yards, and been told by friends in the business that it really is that simple in the end. There is something physically with the fact that it can bend that allows the vapor(?) to eventually make it through.

On our boat also the heads are plumbed to the bottom of the holding tank. So as the tank fills up so do the hoses, just like in a glass sight gauge for a tank. This fluid is in the hoses basically at all times. That's where our scent is originating from. We are going to plug up those intakes and reroute new PVC plumbing to new points on the top of the tank ensuring we have no level or hang up spots along the way. Its what this yard has done with a few other Selenes, and no more problems.
No Mast is offline   Reply With Quote
Old 02-27-2015, 03:56 PM   #18
Guru
 
Rogerh's Avatar
 
City: Niceville, FL
Country: USA
Vessel Name: At Last
Vessel Model: 1990 Jefferson 52 Marquessa
Join Date: Aug 2013
Posts: 665
Wow, they ran the yuk stuff to the bottom of the tank? I can see why you would have oder problems. I would think the PVC to the top of the tank would fix your problems.
Rogerh is offline   Reply With Quote
Old 02-27-2015, 03:58 PM   #19
Member
 
billwilletts's Avatar
 
City: Southport NC
Country: USA
Vessel Name: Jolly Mon II
Vessel Model: Marine Trader 40 Double Cabin
Join Date: Sep 2012
Posts: 8
Yeah that seems like a no-brainer.
billwilletts is offline   Reply With Quote
Old 02-27-2015, 04:01 PM   #20
Guru
 
No Mast's Avatar
 
City: Atlantic Highlands, NJ
Country: US
Vessel Name: Moana Huaka'i
Vessel Model: Selene 53
Join Date: Dec 2014
Posts: 816
yea, I have to say so far the Selene has proven to be an amazing boat. That oversight in design is the only real issue I see, but all things considered, easy to rectify. Can't understand why they would have done that. Oh well...
__________________

No Mast is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 09:08 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012