Hose Fittings & Adapters

Sorting out RV water fittings and adapters

Two jobs live in this category: getting water into the rig, and plumbing it around once it's in. Which fitting you need comes down to what you're connecting and the thread on each end:

• City water inlet vs gravity fill. A city water fill dish, like the Valterra and JR Products units (some with a built-in check valve), is your pressurized hookup. A gravity or telescoping fill spout is the port you pour or hose into to fill the fresh tank directly.
• Thread type. GHT (garden hose thread) is the coarse hose connection; NPT/FPT is the tapered pipe thread inside the plumbing. They don't interchange, so match male to female and coarse to coarse, or you'll cross-thread and leak.
• PEX and quick-connect. Newer rigs run PEX line, so a Flair-It angle stop or a Sea-Tech push-to-connect barb ties in without tools. Confirm the tubing size, usually 1/2", before you buy.
• Splitters and shutoffs. A Y-connector like the Valterra deluxe double shutoff lets you run a wash hose off the same spigot and kill either leg with a dial valve, handy at a shared post.

Match these up with a drinking-safe hose on the supply side and the right pressure regulator ahead of the inlet. If you're chasing a taste problem rather than a leak, the water filters are one category over.