Forum Discussion
myredracer
Oct 29, 2014Explorer II
Red & blue PEX used in RVs is a slightly smaller diameter than residential PEX and I am not 100% certain it is okay to use Sharkbite type fittings. However a lot of folks do that without issue and I have one in our TT as it's what I had on hand when I needed a coupling for a plumbing mod project.
I'm a fan of PEX crimp rings but I have the crimper tool. PEX crimpers can be impossible to get into some tight spaces though, making a compression or sharkbite fitting the way to go.
For another option, you might consider using Qest fittings like here. They have compression type fittings but they also have them that are 1/2" FIP and MIP threads, and if you can source the fittings, you might be able to just thread the fittings right on. The pipe connection to the toilet will be a 1/2" threaded swivel fitting and will just thread right onto a Qest tee, plus you'd need a coupling. Qest fittings are available at RV parts suppliers.
You may or may not have enough room to add the Qest fittings directly behind the toilet. I added a Qest elbow and shutoff behind our toilet and barely had enough clearance. You might also consider installing a shutoff valve at the same time. You should use a PEX tubing cutter to make sure the cut is clean and square to prevent leaks. Don't need a ratchet type and can get one like in the pic for around $5.
Another option would be to get rid of the plastic toilet if you have one, and get a porcelain one. We have one now and it sure is a lot easier to clean. Just money....



I'm a fan of PEX crimp rings but I have the crimper tool. PEX crimpers can be impossible to get into some tight spaces though, making a compression or sharkbite fitting the way to go.
For another option, you might consider using Qest fittings like here. They have compression type fittings but they also have them that are 1/2" FIP and MIP threads, and if you can source the fittings, you might be able to just thread the fittings right on. The pipe connection to the toilet will be a 1/2" threaded swivel fitting and will just thread right onto a Qest tee, plus you'd need a coupling. Qest fittings are available at RV parts suppliers.
You may or may not have enough room to add the Qest fittings directly behind the toilet. I added a Qest elbow and shutoff behind our toilet and barely had enough clearance. You might also consider installing a shutoff valve at the same time. You should use a PEX tubing cutter to make sure the cut is clean and square to prevent leaks. Don't need a ratchet type and can get one like in the pic for around $5.
Another option would be to get rid of the plastic toilet if you have one, and get a porcelain one. We have one now and it sure is a lot easier to clean. Just money....


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