RV plumbing failures cluster around three failure modes: connection failure, freeze damage, and abrasion. This post covers the first.
The three fitting families
Crimp (copper ring) — cheap, easy, requires the right crimper. Failure mode: an undersized crimp slowly weeps. Fix: cut it out, recrimp with calibrated tool.
Expansion (PEX-A) — most reliable for vibration. Failure mode: rare; usually a bad expansion ring not fully seated.
Push-fit (SharkBite-style) — convenient for emergencies. Failure mode: o-ring degradation over years. Not a long-term solution in an RV that lives outside.
Why RVs eat fittings
A house plumbing system never moves. An RV system flexes every time the chassis hits a pothole. Combined with summer heat-soak and winter freeze cycles, fittings work-harden faster than a stationary install.
We replace push-fit with crimp or expansion on every RV we touch. Same labor, dramatically lower failure rate.