ABS vs PVC

[Gkiesel]

Getting ready to replace my dump valves in the old Argosy. All the old drain lines are of course ABS, and all the joints are mostly glued. So my question is should I source out new ABS pipe or go with the more readily available PVC??
Are ther any advantages to ABS over PVC in an Rv application??
Thanks, George

[markdoane]

I can't find any "data", but I believe that ABS is less susceptible to breaking in cold weather.

This is based on some cracked PVC that I had in the garage one winter. I think ABS is also more UV resistant.

I would stick with what the majority of manufacturers use for DWV piping. The ABS fittings aren't hard to find, for some reason a few stores don't carry a wide selection. Other stores will have a wide selection.

[Haoleman]

Hi Mark

ABS used to be used in all residential plumbing but due to toxicity of fumes when burning, the UPC changed to use PVC which in my opinion is equally bad. It is much tougher though and less brittle. If you wack your plumbing on a rock though, it won't matter what you are using as it will probably rip everything off the tank anyway. Most tanks are made of ABS or fiberglass so it's better if you stick with what your tank will accept as far as glue goes. There is a glue that will work with PVC and ABS but there are compatability issues. You will only find it in a plumbing supply house.

Terry

[Tim A.]

ABS used to be used in all residential plumbing but due to toxicity of fumes when burning, the UPC changed to use PVC...

I am certainly not a plumber, but a quick internet check of the Uniform Plumbing Code (UPC) shows that it still discusses ABS pipe for Drain-Waste-Vent (DWV) use. My local hardware stores also still have all kinds of ABS DWV pipe and fittings, so I think you just have to look around (as markdoane says) a bit to find what you need.

[74"Twinkie"]

Hi George, I prefer ABS. In my area ABS is more available. Also, the only waste valves I've seen are ABS.
I have used universal type glue (ABS, PVC, CPVC) to connect PVC and ABS in other applications and would dare anyone to pull them apart. That being said, if I tried this on my trailer it would certainly come apart. (Not a good thought)
Good luck with your project. Dennis

[Gkiesel]

Good morning everyone, Got my new drain valves installed this past weekend. Used ABS to keep it original, but also because others told me about PVC getting brittle in the cold like Markdoane suggested. It's interesting to note that the Thetford valves are PVC, but no real issues arose about gluing them to the ABS. If they were pressure fittings I would probably source out special ABS to PVC glue but, these are definetly not coming apart. The hardest part was making sure everything would line up before glueing and figuring out what order to glue the parts in. You sure don't get a second chance with that stuff! My biggest fear was gluing to the new valve incorrectly and having to buy a new (very expensive) valve again. Now to replace the belly pan. Rally coming up on July 20, so I have to get crackin. Thanks. George.