DI Water vs. Reverse Osmosis for RV Washing
Both reduce dissolved material, but they do different jobs and have different practical tradeoffs on a large coach.
Reverse osmosis
RO pushes water through a membrane and rejects a portion of the supply along with the dissolved material. It reduces dissolved salts but produces a concentrate stream. Output rate depends on pressure, temperature and membrane condition; a storage tank may be needed to meet wash demand.
Deionization
DI uses resin to exchange charged ions and can produce a very low-mineral final rinse at the point of use. It is especially useful when the goal is to let paint and glass air-dry without visible mineral residue.
The RV washing decision
RO can reduce the load reaching a downstream DI stage, or provide sufficiently low-mineral rinse water in some conditions. A spot-free wash needs verified final-rinse quality. For a coach that moves between unknown campground and marina hookups, treatment stages should be chosen around the actual job rather than the product label.
Practical comparison
- RO: membrane treatment with wastewater and equipment requirements.
- DI: point-of-use polishing for a low-mineral rinse.
- For an RV wash, the final rinse quality matters more than choosing the most technical-sounding stage.