Rigid PVC to replace flexible sanitation line?

[idratherbeboating]

I have a crack in my flexible sanitation line and it needs to be replaced. My dealer said he's had good luck with using rigid PVC, although it is a non-traditional solution.

I trust his recommendation and appreciate that rigid PVC ensures zero odor, but I also worry about it's ability to handle the vibration and trials of a marine environment and any other risks of this unusual approach...

Has anyone else had experience (good/bad) with upgrading their sanitation lines to rigid PVC?

If you were shopping for a used boat that had rigid PVC, would you be scared or impressed or not care?

Thanks for your thoughts!

 

[fishheadbarandgrill]

I had a Catalina 380 prior to my R29. Lots of discussion on this topic with Catalina owners. The same points usually come up... concern about vibration. I'd probably be impressed if someone made the switch to PVC. That's a lot of work so you know that the owner loved his/her boat. I replaced the sanitation lines on my Catalina and elected not to use PVC. I used the highest quality sanitation hoses (Trident 101). With proper usage... flushing and what not. Trident hoses will last a long time. Trident hoses are of much better quality than the hoses used by RT from the factory (same comment would be for most production boat builders IMO).

 

[ixlr8]

The Sabre 66 I was helping build used rigid PVC for most sanitation lines. It was a black PVC that was rated for sanitation and was supported every 16 inches. There was appropriately rated flex lines going pumps or anything that might flex.

 

[stwendl]

If you had easy access to the “basement” in a boat and it’s pipes, usually in larger vessels, it’s probably ok. But on our boats with limited space and many curves it would not be a good idea. You really don’t want a leak as there is just no access for cleaning in case of a breakage

 

[Jim and Jackie]

On my last boat a Freedom 38 (sailboat) I had several runs of rigid PVC. In the 8 years in was in the boat I never had a problem. It was well secured and the hose connections provided flexibility.

Jim Demerest
2010 R 29 Chessie

 

[jkhiser]

Wenniway has a run of PVC for the head, starting after the vented loop and ending behind the autopilot pump.

I do not know if this is original or added by the first owner.

 

[Trisailor]

That's an intriguing thought. Since my head has stopped flushing due to a possible pump failure and 7 year old plumbing lines, I may look at a partial pipe run of rigid waste line. Replacing portions of old marine (white) plumbing using abs pipe is attractive. I'm sure the local home box store has plenty of barbed fittings to attach the white pipe to. My only concern is the possibility of bad joints creating spots for the collection of waste debris to form clogs. More years ago than I would like to acknowledge, as an electrician apprentice, we would bend our own 90's and other bends in 1and 1/2" sch 40 conduit. We used a portable "toaster oven" arrangement to heat the pipe. One just had to be careful to not allow the pipe to collapse as it was bent.

 

[Toucan]

When connecting hose to PVC or ABS pipe using hose clamps, the pipe diameter will dramatically shrink under the load with time. After all, the definition of a plastic material is that it will deform over time under a load. I double the thickness of the pipe with half of a coupling fitting glued over it. The diameter shrinkage over time is substantially minimized when doing this. Just make sure that you can get to the hose clamps to periodically retighten them. Glue joints will also crack under stress after a few years. All my experience with plastic pipe to hose joints comes from maintaining swimming pool plumbing, including solar pool heaters. I will stick with sanitation hose on our boat.

Barry Thompson

 

[TexasEye]

When connecting hose to PVC or ABS pipe using hose clamps, the pipe diameter will dramatically shrink under the load with time. After all, the definition of a plastic material is that it will deform over time under a load. I double the thickness of the pipe with half of a coupling fitting glued over it. The diameter shrinkage over time is substantially minimized when doing this. Just make sure that you can get to the hose clamps to periodically retighten them. Glue joints will also crack under stress after a few years. All my experience with plastic pipe to hose joints comes from maintaining swimming pool plumbing, including solar pool heaters. I will stick with sanitation hose on our boat.

Barry Thompson

Yep, and a boat rocks and rolls more than a swimming pool, well, except in California...designers are normally pretty smart!

Tex